This eye-catching astronaut photo shows the fractured surface of the world's highest frozen lake lurking in the lofty climbs of the Tibetan Plateau. The smooth, white line where the ice meets the water closely follows a disputed border between China and India.

The elevated lake, known as Pangong Lake or Pangong Tso, sits at an altitude of 13,862 feet (4,225 meters), according to NASA's Earth Observatory. It is long and thin, stretching 83 miles (134 kilometers) across Ladakh, part of the Kashmir region administered by India; and Tibet, an autonomous region of China.

This photo shows a roughly 9.5-mile-long (15 km) section of the river, located around a third of the way along its length from west to east. This is also where the most widely accepted border between Ladakh (on the left of the photo) and Tibet (right side of the photo) lies. However, the exact position of the divide, commonly known as the Line of Actual Control, is poorly defined and has shifted in recent decades, according to The New York Times.

Pangong Lake is endorheic, meaning it has no outflow, and the only way water can escape is via evaporation. As a result, the lake's waters have built up an unusually high concentration of salt over thousands of years. This would usually prevent it from freezing. However, the temperature in the region can drop to minus 13 degrees Fahrenheit (minus 25 degrees Celsius), according to a local travel site, which is cold enough for the salty water to freeze over.

It is unclear why the lake's ice is fracturing in the photo. Normally, the entire body of water is completely frozen in January, when this photo was taken in 2024.

Although Pangong Lake has no major outflow, it is connected to several inflowing rivers, including one on the bottom left of this image. The river's delta has largely frozen over (visible as the large, white patch on land), but you can still see a small plume of water entering the river.

On the opposite bank of the delta, there is a beach littered with several striations parallel to the water. These are ancient shorelines left over from when the lake had a higher water level, according to the Earth Observatory.

Pangong Lake was likely once part of the Indus River, which stretches nearly 2,000 miles (3,200 km) across South and Central Asia. However, it was likely cut off from the waterway millions of years ago as the Indian and Eurasian tectonic plates collided and the Tibetan Plateau and Himalayas formed.

Disputed border

The Line of Actual Control was first established in 1959 but was largely set in its current position in 1962 after the Sino-Indian War. Although the countries have technically been at peace ever since, frequent and occasionally deadly skirmishes have broken out along the border, including on the shores of Pangong Lake, according to the BBC.

Nonetheless, the lake frequently draws tourists from both China and India, particularly bird-watchers, who travel there to see the large groups of bar-headed geese (Anser indicus) and Brahminy ducks (Tadorna ferruginea, also called ruddy shelducks) that breed there, according to the Earth Observatory.

On the Ladakh side of Pangong Lake, extreme-sports enthusiasts run long distances across the lake's ice. In February 2023, dozens of runners gathered there to participate in the highest-altitude frozen lake half-marathon ever recorded, according to Guinness World Records.

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This striking satellite photo shows a multicolor "fan" of folded rocks sculpted by a longtime collision between two of Earth's tectonic plates.

The geological feature, known as an imbricate fan, is located around 3 miles (5 kilometers) east of the town of Murgha Kibzai in Pakistan's Balochistan province. The photographed section of folded rocks measures around 9 miles (15 km) across, but the fan stretches up to 55 miles (89 km) from end to end, well beyond the area in this image.

The dramatic structure sits at an altitude of around 5,000 feet (1,500 meters) in the Sulaiman Range, a series of mountains that covers around 2,500 square miles (6,500 square kilometers) of Pakistan and Afghanistan. ("Sulaiman" means "of Solomon," in reference to the biblical figure King Solomon, and the range's largest peak is Takht-e-Sulaiman, which translates to "Throne of Solomon.")

This is one of several unique features that emerged along the boundary between the Eurasian and Indian tectonic plates, which have been colliding for more than 60 million years. At one point during this tectonic tug-of-war, the two plates became somewhat intertwined, allowing the fan to take shape, according to NASA's Earth Observatory.

"As India moved northward, it began to rotate in a counter-clockwise direction, wrenching the northwestern part of the Indian plate backwards into part of the Eurasian plate," Earth Observatory representatives wrote. "The countervailing forces put the rocks of the Sulaiman Range in a unique compressional vice, causing many of its faults to curve and stretch in convoluted ways."

The fan is made up of alternating layers of sandstone, which appear dark in the image, and limestone, which has a much lighter hue. These sedimentary rocks were formed by "thrust faults" that shot upward from the boundary between the Eurasian and Indian plates and became entangled as the boundary moved back and forth.

The satellite image is false-color, meaning it includes wavelengths of the electromagnetic spectrum that are not normally visible to humans. This helps to accentuate the differences between the two rock types, although they can also be easily distinguished with the naked eye. Pockets of vegetation appear in red throughout the image.

The photo is a small part of a larger, wide-field image (see above), which showcases several other intriguing geological features across the Sulaiman Range in false color.

Continental collision

The collision between the Eurasian and Indian plates became inevitable around 80 million years ago, when dinosaurs still ruled Earth, according to the Earth Observatory. At this point, the pair became locked on a collision course, with each plate moving more than 8 inches (20 centimeters) per year — around twice the speed of the fastest tectonic plates today.

Around 60 million years ago, the plates slowly slammed together. Normally, this would cause the smallest tectonic plate to sink below the other. However, the two plates' massive size meant neither receded. Instead, the continental crust along the boundary grew thicker, and the ground buckled, folded and pushed upward.

This process created not only the Sulaiman Range but also the Karakoram (a huge mountain range that spans the borders of China, India, Pakistan, Tajikistan and Afghanistan) and the Himalayas — the two tallest mountain ranges on Earth, according to the Earth Observatory.

This collision continued at full speed for around 30 million years, before eventually slowing down. However, the two plates are still technically colliding today, making the region a major earthquake hotspot.

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This eye-catching astronaut photo shows a cloud of sediment swirling into a giant, milky-green vortex in one of Europe's largest lakes.

Lake Skadar (also known as Shkodër, Shkodra or Scutari) is the largest lake in Southern Europe, with a surface area between 140 and 200 square miles (360 to 520 square kilometers), depending on the time of year. It is situated on the border between Montenegro, which surrounds the western half of the lake (left in the photo), and Albania, which encircles the lake's eastern shore. The body of water is split 65% to 35% in Montenegro's favor.

The lake's main water source is the Morača River, to the northwest, and its biggest outlets are the Bojana and Drin rivers, which start at the lake's easternmost point and eventually drain into the Adriatic Sea, which is partially visible in the bottom left of the photo. Skadar's southern shore is also hugged by a lofty mountain range, known as the Dinaric Alps.

During late winter and early spring, the lake's water level rises, and it usually fills with a milky-green substance that often gets whipped into a vortex by a combination of wind-driven surface currents and the natural flow of water between the lake's major inlets and outlets.

The swirling material looks very similar to blooming algae, but it is actually made of sediments — predominantly limestone and dolomite — that wash into the lake from the Dinaric Alps and other nearby mountains as the snow melts.

Skadar is a karst lake, meaning it was once a cave system that flooded and eventually collapsed, likely because the caves were made from the same easily erodible rocks that now swirl on the lake's surface, according to NASA's Earth Observatory. The lake is a "cryptodepression" because most of the lake's floor is below sea level.

The lake originally formed during the Cenozoic Era (66 million years ago to the present), according to the International Lake Environment Committee Foundation's World Lake Database. It is home to several small islands, some of which can be seen in the photo along the lake's southern shore. These include Beška, which is home to a pair of 600-year-old churches, and Grmožur, where the remains of a 19th-century fortification loom above the lake's surface.

The shipwreck of a paddle steamboat, named Skanderbeg, lies along the lake's western shore. Local partisans sank the vessel in 1942 after Italian soldiers commandeered it during the Axis occupation of Yugoslavia in World War II. When the lake's water levels are at their lowest, part of the shipwreck rises above the surface.

Skadar Lake is a biodiversity hotspot and has protected wildlife status on both sides of the Montenegro-Albania border. It is a particularly important site for birds; more than 280 avian species call it home, including the Dalmatian pelican (Pelecanus crispus) and several endemic species, according to BirdLife International.

The lake also hosts around 50 freshwater snail species ‪—‬ more than any other lake on Earth, according to a 2013 study.

This stunning astronaut photo shows the last time one of NASA's iconic space shuttles photobombed astronauts' view of Earth as the spacecraft docked with the ISS.

NASA's Space Shuttle Program included five plane-like spacecraft — Columbia, Challenger, Discovery, Atlantis and Endeavour — which collectively completed 135 missions between 1981 and 2011, racking up more than 32,000 hours in space. During that time, they helped to construct the ISS and, later, ferry astronauts to and from the station. The space shuttles also helped to deploy and maintain several other important spacecraft, including the Hubble Space Telescope.

The last space shuttle to fly was Atlantis, which successfully completed 33 missions (the second-highest total, behind Discovery).

This photo shows Atlantis approaching the ISS for the last time as it passed over the distinctive turquoise waters of the Bahamas. The space shuttle's bay doors are open, exposing its cargo area. This was standard procedure for all space shuttles once they reached low Earth orbit because it prevented the spacecraft's radiators from overheating.

The open doors also enabled the shuttle's docking mechanism, located within its cargo bay, to attach to the ISS, thus creating a pressurized seal so that astronauts could move between the two spacecraft.

Atlantis' final flight began on July 8, 2011, when it launched from the Kennedy Space Center in Florida vertically strapped to a massive fuel tank and a pair of rocket boosters. It returned to Earth on July 21, gliding down to land onto a runway at the launch site. (The spacecraft is now on display at the Kennedy Space Center Visitor Complex.)

In addition to helping construct the ISS, NASA's space shuttles visited Russia's Mir space station, serviced Hubble, and deployed both the Magellan probe to Venus and the Galileo probe to Jupiter. In total, the space shuttle orbited Earth 4,848 times, traveling nearly 126 million miles (203 million kilometers) — more than 525 times the distance between Earth and the moon.

Astronaut photos of the space shuttles were popular because they offered "punctuated snapshots of distinct places on Earth" that were "framed by a human eye," NASA representatives wrote in 2011. "These images speak to people."

While the Space Shuttle Program achieved a lot during its 30-year history, it famously suffered two tragedies: the 1986 Challenger and 2003 Columbia disasters, which killed all crewmembers on board.

NASA eventually canceled the program in 2011, citing the high cost of maintaining the aging spacecraft and a reduced need for the vehicles after the completion of the ISS the same year. To this day, the space shuttles remain the only winged spacecraft to carry humans into space.

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This ethereal satellite snap shows beautiful, "painting-like" folds within an ancient underwater structure in the Bahamas.

The Great Bahama Bank (GBB) is a massive submerged platform stretching around 330 miles (530 kilometers) across a shallow ocean channel between Andros Island and the Exuma islands, according to Britannica. The crescent-shaped bank surrounds a darkly colored ocean drop-off known as "The Tongue of the Ocean," which plunges to depths of 6,500 feet (2,000 meters), according to NASA's Earth Observatory.

The photographed section of the GBB is around 23 miles (37 km) across and features a series of submerged sandbanks — most of which are covered with dense seagrass beds — that lie between 7 and 40 feet (2 to 12 m) below the ocean's surface.

The varying water depth and seagrass concentration cause multiple hues of green and blue to shine across the sandbanks, which have been carved into smooth, folding ribbons by ocean currents over thousands of years.

"The varying colors and curves remind us of graceful strokes on a painting," Earth Observatory representatives wrote.

This section of the GBB was first photographed in 2001 by the Landsat 7 satellite and has often appeared on lists of the most iconic aerial images of our planet.

"There are many nice seagrass and sand patterns worldwide, but none like this anywhere on Earth," Serge Andréfouet, an oceanographer at the French National Research Institute for Sustainable Development who first shared the 2001 image, told the Earth Observatory. "I am not surprised it is still a favorite, especially for people who see it for the first time."

The sandbanks are like giant underwater dunes carved out by ocean currents.

"Tides and ocean currents in the Bahamas sculpted the sand and seaweed beds into these multicolored, fluted patterns in much the same way that winds sculpted the vast sand dunes in the Sahara Desert," Earth Observatory representatives wrote in 2001.

The GBB lies atop a roughly 3-mile-thick (5 km) bed of limestone dating to the age of the dinosaurs, more than 65 million years ago. This hefty mass, made up of the remains of long-dead coral reefs, is so large that Earth's crust directly below the GBB has "sagged under the weight," according to the University of Texas at Austin's Marine Science Institute.

Before the end of the last ice age, around 12,000 years ago, this limestone slab had risen to more than 400 feet (120 m) above sea level and only resubmerged as global sea levels rose due to the melting of glaciers, according to the Marine Science Institute.

The Bahamas has more than 3,000 islands and smaller cays and is home to several other intriguing oceanographic features, including deep tidal channels off the coast of Great Exuma Island (which once harbored famous pirate ships) and a series of aurora-like sandbanks that appear to shine along the nation's northernmost islands.

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This eye-catching satellite snap shows off a sprawling mass of petrified lava surrounding the jet-black slopes of a potentially dangerous volcano in the heart of the Sahara. A smaller volcanic "skull" lurks near the shadowy peak's base.

Toussidé (also known as Tarso Toussidé) is a "potentially active" stratovolcano located within the Tibesti Mountains, which cover around 40,000 square miles (100,000 square kilometers) of northern Chad and southern Libya. The dark peak stands 10,712 feet (3,265 meters) above sea level, making it the second-tallest mountain in the Tibesti region.

The name Toussidé roughly translates to "which killed the local people with fire" in the language of the nearby Indigenous people, hinting at a destructive and deadly history. However, according to the Smithsonian Institution's Global Volcanism Program, there is no evidence that the volcano has erupted during the Holocene — the current geological epoch, which began around 12,000 years ago. It is unclear if it has actually killed anyone.

The dark blob surrounding the volcano is known as a massif. It is made up of layers of overlapping magmatic rock left by multiple ancient lava flows that effusively erupted, or slowly poured from, the volcano's summit.

The shadowy structure, which is up to 20 miles (32 kilometers) across at its widest point, stands out against the surrounding sand-covered plateau, which has been carved into a network of crisscrossing canyons by eons of wind blasting, according to NASA's Earth Observatory.

Just southeast of the massif (in the upper right of the photo), there is a small, white circle containing several dark patches. This is Trou au Natron — a roughly 3,300-foot-deep (1,000 m) volcanic crater, or caldera, which looks eerily like a giant skull when viewed directly from above.

The cranium-like caldera likely formed during an explosive eruption more than 120,000 years ago. It was once filled with a giant salt lake that was home to ancient algae and other microorganisms. When the lake dried out, around the start of the Holocene, the receding water left behind a thick layer of white salt surrounding a pair of eyelike volcanic cones.

Toussidé is one of the youngest mountains in the Tibesti range, which formed by similar effusive eruptions long before the stratovolcano was born. The entire region likely once matched the massif's dark hue before being relentlessly bombarded by sand and wind. In another 100,000 years or so, the massif may blend in with the surrounding plateau, according to the Earth Observatory.

While the shadowy volcano has remained dormant for several millennia, it occasionally puffs out steam from small vents, or fumaroles, near its summit, suggesting that it is still technically active, according to the European Space Agency. However, geologists have not properly assessed its eruptive potential.

This eye-catching satellite snap shows off a "bull's-eye-like" set of concentric cloud rings that formed above an erupting volcano on La Palma in Spain's Canary Islands.

The eruption, the first on La Palma in 50 years, began Sept. 19, 2021, when a fissure opened up on the western flank of Cumbre Vieja — a volcanic ridge that runs through the southern half of the island — and spewed massive lava fountains into the air. The violent outburst created a 660-foot-tall (200 meters) vent, dubbed Tajogaite, which continued to slowly pump out lava until Dec. 13, 2021.

The molten rock flowed into the Atlantic Ocean in a giant "river of fire" that destroyed a town and unleashed deadly gases that are still causing issues for locals today, Live Science previously reported.

The concentric cloud rings in this image are made up of steam, smoke and ash ‪—‬ known as an eruption plume ‪—‬ that rose above Tajogaite for weeks.

Normally, such a plume would continue to climb into the cold air of the stratosphere — the second layer of the atmosphere, which extends from around 6 to 31 miles (10 to 50 kilometers) above Earth's surface. However, when this image was captured, a rare "temperature inversion" created a layer of elevated warm air that acted as a lid, preventing the plume from rising and forcing it to spread outward, according to NASA's Earth Observatory.

The trapped plume created concentric rings that formed from the natural ebb and flow in the intensity of volcanic activity. This pulse in the emissions given off by the volcano is visible in time-lapse footage captured by the Izaña Atmospheric Research Center on Tenerife, another Canary Island.

The official name for this type of concentric cloud formation is a "gravity wave," according to the National Weather Service. However, the formation has nothing to do with gravity, and it's completely separate from the ripples in space-time called gravitational waves.

"River of fire"

During the 85-day eruption, around 7.1 billion cubic feet (200 million cubic meters) of lava — reaching temperatures of up to 2,000 degrees Fahrenheit (1,100 degrees Celsius) — seeped from the ground.

This molten rock traveled around 4 miles (6.4 kilometers), destroying around 3,000 buildings in the town of Todoque, before falling into the Atlantic Ocean in a fiery waterfall. The estimated damage exceeded 700 million euros ($780 million), according to the Spanish newspaper El País.

Where lava fell into the sea, around 4.6 million square feet (430,000 square meters) of new land was created. The reaction between the molten rock and the water also released high levels of volcanic gases, such as sulfur dioxide and hydrogen cyanide.

At least one person, a 72-year-old man who returned to his home prematurely, is believed to have died from inhaling these toxic fumes, according to AFP. Thousands of wild and agricultural animals are also thought to have been killed by the gases.

The damage was "truly terrible," Marie Edmonds, a volcanologist at the University of Cambridge, told Live Science at an event on La Palma in April 2025. "Most shocking to me is the closeness of the vent to the communities," she added when describing what it was like to visit the area. "It must have been absolutely terrifying to see the eruption so close."

This awesome astronaut photo shows the striking symmetry of "twin" stratovolcanoes at the heart of Java, Indonesia. The parallel peaks are an eye-catching reminder of the region's extreme tectonic activity.

Mount Sundoro (also known as Sindoro or Sindara) on the left of the image, reaches a maximum height of 10,331 feet (3,149 meters). Its partner, Mount Sumbing, sits to the southeast (on the right of the image) and is slightly taller, at 11,056 feet (3,370 m) above sea level.

Both are considered active. Although Sumbing has not erupted since 1730, Sundoro has blown its top more recently, in 1971, and has experienced seismic activity as recently as 2012, according to the Smithsonian Institution's Global Volcanism Program.

The volcanoes' peaks are just 7.5 miles (12 kilometers) apart. A raised ridge with a major highway runs perpendicularly between them.

Each volcano also has a smaller, secondary cone on its flank left over from previous eruptions (to the upper left of Sundoro and the upper right of Sumbing in the image), and their orientations make the volcanoes look like mirror images of each other.

The slopes of both cones are covered with rings of dark-green forest that sharply terminate at their bases. The volcanic soils surrounding the mountains are excellent for growing crops such as rice, corn, coffee and sugarcane, which has led to the deforestation of their surroundings, according to NASA's Earth Observatory.

This matching coloration accentuates the similarities between the pair, especially when viewed from above.

One of the few differences between Sundoro and Sumbing is that the latter volcano has a sizable crater at its summit, which was carved out by the 1730 eruption. As a result, the larger volcano appears to have a darker point at its top.

The volcanoes are commonly referred to as "twins," due to their near-identical profiles. However, local people often call them "husband and wife," according to a local travel site. In this narrative, Sumbing is considered the husband due to its slight height advantage and "more masculine" profile.

Sundoro and Sumbing are part of the wider Dieng Volcanic Complex, which consists of around 20 volcanic cones stretching across central Java. Indonesia is also positioned along the "Ring of Fire," a roughly horseshoe-shaped arc of volcanoes that runs along a series of tectonic plate boundaries encircling the Pacific Ocean.

Over the past few years, there have been a number of significant eruptions in Indonesia, including a pair of violent blasts at Mount Lewotobi Laki-laki, on Flores Island, in 2024 and 2025. As of June 2026, there are seven ongoing eruptions in Indonesia — the most of any nation.

This dramatic astronaut photo shows a trio of colorful lakes straddling the border between Nevada and California. The three lakes ‪—‬ which vary in shape, size and salinity ‪—‬ also occupy very different biomes.

The most famous lake in the trio, Lake Tahoe (on the left), is the largest alpine lake in the U.S.. It covers an area of around 192 square miles (497 square kilometers) and sits at about 6,223 feet (1,897 meters) above sea level in the Sierra Nevada, which stretches across the bottom of the image and is covered in snow.

The other two bodies, Walker Lake (upper right) and Mono Lake (lower right), are positioned southeast of Lake Tahoe and each have have a maximum width of around 13 miles (21kilometers). (Another major body of water, Pyramid Lake, is located out of the shot to the northeast of Lake Tahoe, while two much smaller lakes sit between the three larger lakes.)

The border between California and Nevada runs directly through the middle of Lake Tahoe and continues to bisect the space between Walker Lake, which is in Nevada, and Mono Lake, which is in California.

While Tahoe is located in the lofty climbs of the Sierra Nevada and is subsequently exposed to very wet and cold conditions, Walker and Mono are situated within the Great Basin desert. This flatter region — which also covers parts of Utah, Idaho and Oregon — has a drastically different environment because it sits within the mountain range's "rain shadow" and, therefore, receives very little precipitation, according to NASA's Earth Observatory.

The other stark difference between the lakes is their respective colors, which become even more apparent when viewed from above.

Lake Tahoe is the second-deepest lake in the U.S., with a maximum depth of 1,645 feet (501 m). As a result, it has a rich, bright-blue hue. It has constant subsurface currents that prevent it from freezing over in the winter, so it looks the same year-round.

Walker Lake is endorheic, which means it does not have a proper inlet or outlet and instead rises and falls via rainfall and evaporation. Over the past few centuries, the rate of evaporation has outpaced precipitation, which has made the lake extremely salty, or hypersaline. This altered chemistry, combined with the lake's shallower waters and the presence of various microbes, gives the lake a greener hue when viewed from above.

Mono Lake is also endorheic. It has seen an even sharper drop-off in recent years, as evidenced by a series of "bathtub rings" left over from when the lake had much higher water levels. It's home to salt-tolerant photosynthetic algae, which are preyed upon by brine shrimp (Artemia). Drops in the shrimp population in the colder winter months allow the algae to bloom, causing Mono Lake to turn bright green. If you look closely at the image of the lake, you can see a large swirl that represents the blooming algae getting trapped within wind-driven surface currents.

Due to the sharp rises in their salinity, Walker and Mono lakes have almost no remaining fish populations. This has allowed algae to take a greater hold in both lakes, according to the Mono Lake Committee.

Mono Lake also made headlines in 2010 when NASA scientists found a species of bacteria living there that could feed on the high levels of arsenic in its waters — a first in microbe biology, which could "impact the search for evidence of extraterrestrial life," researchers claimed. However, this paper was eventually retracted in 2025 after experts noticed flaws in its data.

Although it is rare to see many visually contrasting lakes in close proximity, similar scenes have been snapped from space. For example, in Africa's Great Rift Valley, there is a striking trio of blue, green and yellow lakes. Colorful collections of lakes can also be found in Crimea's "putrid sea" and around the Etosha Pan in Namibia.

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In this striking satellite photo, rusty-orange water appears to bleed across the salty white floor of a high-altitude lagoon in Bolivia.

Laguna Colorada ("Red Lagoon" in Spanish) is a hypersaline, or extremely salty, lake in Bolivia's Altiplano — the world's second-highest plateau, which stretches across the Andes. It sits around 14,100 feet (4,300 meters) above sea level.

The lagoon was once much larger, which is evident thanks to the striations of an ancient shoreline visible along its right edge. As it eventually dried out, an uneven layer of borax salt (sodium tetraborate) was left behind. These salty crystals often rise above the water level, creating bright-white islands and causing the "bleeding" effect when viewed from above.

The water's reddish hues come from algae, predominantly Dunaliella salina. This salt-loving species is rich in red pigments known as carotenoids, and is responsible for creating similarly reddish waters across the globe.

The lake is often much redder. However, the water's hue changes based on its temperature and salinity, which determine the growth of various alga species, according to NASA's Earth Observatory. At some points in the year, the color is greenish.

Laguna Colorada has been listed as a "wetland of international importance" since 1990 under the Ramsar Convention. Its surroundings are home to a number of animals, including mountain cats, foxes and llamas. However, its most famous residents are flamingos.

At least three species of the bright-pink birds — the Andean flamingo (Phoenicoparrus andinus), the Chilean flamingo (Phoenicopterus chilensis) and the James's flamingo (Phoenicoparrus jamesi) — frequent the lagoon and get their vibrant coloration from eating the carotenoid-rich algae. (Flamingos are born gray; their iconic hue comes from their diet.)

The lagoon sometimes draws comparisons to Tanzania's Lake Natron, which often has blood-red water and is home to 2.5 million of the pink birds — the largest flamingo colony on Earth.

Laguna Colorada is sandwiched between two volcanoes, just out of view at the top and bottom of this photo.

Several other colorful salt lakes are nearby, including Laguna Verde ("Green Lagoon) and Laguna Blanca ("White Lagoon"), which sit side by side around 40 miles (65 kilometers) south of Laguna Colorada.

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This shimmering satellite image shows tendrils of gold surrounding Ghana's sacred "lake of souls," which was carved out by a devastating asteroid strike around 1 million years ago.

Lake Bosumtwi (also spelled Bosomtwe) spans 19 square miles (19 square kilometers) ‪—‬ a little smaller than Manhattan ‪—‬ and is located just to the southeast of Ghana's second-largest city, Kumasi (partially visible in the top left of the photo). The roughly circular body of water, which is up to 240 feet (70 meters) deep, is the country's only natural lake.

To the Indigenous Asante people, the lake is a sacred site. According to their mythology, a hunter named Akora Bompe chased a wounded antelope into a small magical pond, causing the small body of water to rapidly swell into the lake we see today. It is also considered a "place where souls bid farewell to Earth before entering the afterlife," according to NASA's Earth Observatory.

In reality, the lake actually formed around 1 million years ago, when a roughly 3,300-foot-wide (1 km) meteor slammed into our planet, creating "arguably the best-preserved complex young impact structure known on Earth," according to the International Commission on Geoheritage.

The catastrophic collision likely triggered "a blinding flash of light and an immense fireball [that] would have incinerated life for dozens of kilometers," Marian Selorm Sapah, a senior lecturer in the University of Ghana's Department of Earth Science, told the Earth Observatory. If the same event occurred today, it would likely obliterate the city of Kumasi, she added.

Remote sensing analysis has revealed that the material blasted out of the impact settled in a raised, lobed pattern known as a "rampart" crater. This suggests the area was covered in a layer of groundwater when the collision occurred, according to the Earth Observatory.

Rampart craters are rare on Earth but are more common throughout the solar system, including on Mars, as well as on smaller bodies, such as Ganymede, Dione, Tethys and Charon. As a result, studying Lake Bosumtwi could provide insight into how these extraterrestrial craters formed, Sapah said.

The impact also fractured Earth's crust and allowed mineral-rich magma to rise to Earth's surface, forming shallow veins of gold and other valuable elements that have been mined for generations. This activity has resulted in the golden flecks and lines visible in this satellite image.

The rate of gold mining has accelerated in recent years due to advances in technology. Another satellite photo taken in 2024 (see below) shows much more visible gold, which has been exposed by this increased activity. (The lake also appears green in the newer photo due to higher concentrations of phytoplankton in its waters.)

"The stark visual evidence of anthropogenic [human-caused] change juxtaposed with a million-year-old geological landmark is striking," Sapah said.

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This eye-catching astronaut photo shows a series of bright-blue "potash ponds" near the dark-green bends of the Colorado River as the waterway winds through the rocky plateaus of southeast Utah.

The multicolored stripes are solar evaporation ponds, which are located around 8 miles (13 kilometers) southwest of the town of Moab in the heart of the Colorado Plateau — a roughly 130,000-square-mile (340,000 square kilometers) elevated region spanning parts of Colorado, Utah, New Mexico and Arizona.

The photo shows 23 ponds, grouped into two larger structures, which cover a total area of around 400 acres (160 hectares), according to NASA's Earth Observatory. The ponds are used to refine potassium chloride, also known as potash, which is mined at a site just out of view (below the ponds in the image).

The potash is mined by pumping boiling water into the ground to create a mineral-rich brine that is extracted and transported to solar evaporation ponds, where it is reduced into tiny, brown crystals. The distinct colors of the ponds signify that they are at different points in the evaporation process.

When the ponds are initially filled, workers add a dark-blue dye to the water to help it absorb more sunlight, thereby speeding up the rate of evaporation. However, this dye also evaporates, so as the water level drops, the intensity of the blue decreases. Eventually, the ponds turn white and then tan when a dried layer of potash is all that remains.

Potassium sulfide is mainly used as an agricultural fertilizer but has a variety of other industrial applications, including in the production of medicines, cement, fire extinguishers, textiles and beer.

The term "potash" is derived from "pot ash," which is the name of a preindustrial fertilizer made by combining wood ash with water and evaporating the mixture in a pot. The element potassium was subsequently named after pot ash when it was discovered to be the secret main ingredient in this mixture.

In addition to the usual environmental effects of mining, which include habitat destruction and noise pollution, potash mining produces high levels of waste products, such as sodium chloride and clay, which can cause damage to the environment.

This salty sludge is often piled into large mounds or dumped into tailing pools. A 2017 study found that the sludge is sometimes washed into nearby waterways. This can "significantly alter biological communities" and trigger harmful algal blooms. However, it is currently unclear what, if any, effect potash mining is having on the Colorado River.

The Colorado River is the sixth-longest river in the U.S. and stretches around 1,450 miles (2,330 km) from its source in the Rocky Mountains of northern Colorado to the Gulf of California in northern Mexico. The lengthy waterway, which played a role in forming the Grand Canyon, appears green from above due to high levels of suspended sediment, much like in the aptly named Green River — a tributary of the Colorado River that also runs through Utah.

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This striking satellite snap shows a powerful hurricane bearing down on Hawaii as a shimmering silver streak obscures the tropical islands from view.

The swirling cyclone, dubbed Hurricane Kiko, was a Category 4 storm that formed in the eastern Pacific on Aug. 31, 2025. Three days later, on Sept. 3, it had fully strengthened, reaching peak wind speeds of around 145 mph (233 km/h), and made headlines after researchers realized it was on a collision course with Hawaii.

Luckily, the hurricane weakened to a Category 2 storm before reaching Hawaii and diverted to pass mostly north of the islands, before finally fading away on Sept. 10, just off the coast of Honolulu, according to Zoom Earth. These changes, which were brought about after the hurricane hit a patch of cold water, meant that residents experienced some heavy rainfall and high winds but were otherwise unaffected.

The satellite photo was snapped Sept. 7, when Kiko was around 600 miles (965 kilometers) east of Hilo on Hawaii's Big Island, according to NASA's Earth Observatory. At this point, the cyclone was approximately 470 miles (750 km) across at its widest point.

You can just about make out the outlines of the cloud-covered Hawaiian Islands within the thick band of silver stretching across the left side of the image. This shimmering streak is the result of a phenomenon known as a sunglint.

Sunglints are visible only from space. A sunglint occurs when sunlight bounces off the surface of the ocean or another large body of water directly into the observer's line of sight. (This is similar to how sunlight reflects off water during a sunset.)

The phenomenon gives water a metallic, mirror-like appearance, which can create stunning spectacles, such as reflected cloud murals and visually transformed rivers.

What's more, sunglints can partially obscure satellite imagery, thus interfering with efforts to monitor the climate, according to NASA. On the other hand, sunglints can help researchers by revealing hidden oceanographic phenomena, such as subsurface currents and "internal waves."

Researchers predict that, on average, hurricanes and other tropical storms will become more frequent and powerful in the coming decades as a result of human-caused climate change. In fact, there have already been signs of this happening in recent years, including storms such as Hurricane Melissa, which killed 95 people as it ripped through Cuba, Haiti, the Dominican Republic and Jamaica in October 2025.

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Contrasting satellite snaps show the drastic transformation of an emoji-like lake in Canada that completely drained after its bank suddenly collapsed. Experts think a multitude of factors led to the rare event.

Lake Rouge (known locally as Lac Rouge) was a roughly 1-square-mile (3 square kilometers) lake in southwest Quebec. It was positioned next to a pair of smaller, unnamed lakes, each around 1,600 feet (500 meters) across at its widest point. When viewed from above, the three bodies of water looked surprisingly like a shocked face, with the smaller lakes being the eyes above a wide-open mouth.

In May 2025, members of the Cree First Nation of Waswanipi — a nearby community of Indigenous people who used the lake for hunting, fishing and trapping — discovered that the lake had been totally emptied, after they found a thick coating of mud and dead fish spread across a nearby logging road, according to a statement released by the group.

After members of the Cree First Nation of Waswanipi traced the muddy trail back to its source, it became clear that Lake Rouge's eastern bank had collapsed in a landslide-like event, causing its entire water supply to spill outward in a violent torrent known as an "outburst flood." (The two smaller lakes next to Lake Rouge remained unaffected.)

"It looks like a natural disaster," Irene Neeposh, chief of Waswanipi, told CBC News at the time. "We've never seen anything like this."

Satellite imagery shows that the lake's sediment-laden water traveled around 6 miles (10 kilometers) before reaching the larger Doda Lake, which has a surface area of around 29 square miles (75 square km). Rather than flowing along any existing pathways, the water "punched through a row of smaller lakes and ponds" to reach its final destination, according to NASA's Earth Observatory.

The sediment in the water quickly spread throughout Doda Lake, turning the larger body of water into a massive, muddy puddle. The nearby Father Lake (also called Priest Lake), which is around the same size as Doda Lake, was not impacted by the sediment, despite being adjacent to the polluted waterway.

While the exact timing of the outburst flood is unknown, additional satellite imagery revealed it must have occurred between April 29 and May 14, 2025, Live Science's sister site Space.com previously reported.

Researchers told The Guardian that it is extremely rare to see an outburst flood in anything other than glacial lakes or human-made reservoirs, which have banks made of ice or concrete that can suddenly crack and break apart.

Initially, experts assumed the lake bank's collapse was simply due to that winter's large snowfall, which led to an unusually high water level. However, it soon became clear that other factors were at play.

First, the area surrounding Lake Rouge was significantly impacted by major wildfires in 2019 and again in 2023, which was one of the worst years for wildfires in the country's history. This unprecedented wildfire season removed vegetation from the area, making the topsoil less stable. What's more, scorched earth does not readily absorb water, so it could not reduce the pressure applied to the banks as it otherwise would.

Second, the forests around the lake have been largely cleared by logging activities in recent decades, which has led to snow melting faster. This means bodies like Lake Rogue fill up much more quickly than they otherwise would.

Parts of Canada's landscape, including Quebec, are also less resilient to environmental stressors because they were largely covered by a massive ice sheet until around 20,000 years ago.

"It's a very young landscape that's evolving very fast," François-Nicolas Robinne, a forest hydrologist with the Government of Alberta, told The Guardian. If the lake's collapse hadn't happened in 2025, it may have occurred the next year or "a century from now," but it would have happened eventually, he added.

Some researchers, including Robinne, likened the outburst flood to a 2024 incident in British Columbia's Chilcotin River, where a landslide completely dammed the waterway and briefly trapped a population of endangered salmon on the wrong side.

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This beautiful satellite snap captured a series of "brushstroke-like patterns" that emerged in the mouth of an Indonesian river. The striking striations were triggered by a particularly high tide following a full "Strawberry Moon."

The Rokan River is a roughly 220-mile-long (350 kilometers) waterway on Indonesia's Sumatra island. The landmass covers around 170,000 square miles (440,000 square kilometers) in the Indian Ocean, making it the sixth-largest island on Earth.

The river runs from the Barisan Mountains in Sumatra's west to the island's north coast, where it drains into the Strait of Malacca. Here, the river morphs into a brackish estuary that flows on each side of Halang Island (photographed).

The Rokan River often has a yellow hue due to high levels of sand and silt in its waters. The sediment gets dragged up from the river's floor, partially due to the constant rising and falling of the tide, according to NASA's Earth Observatory.

In this image, the tide is on its way out, which causes the sediment to be slowly dragged out to sea. When viewed from above, these "brushstroke-like patterns" transform the river into what looks like an abstract painting, Earth Observatory representatives wrote.

When the photo was taken, the high tide was at its peak ‪—‬ up to 16 feet (5 meters) higher than low tide. The water was especially high because it was the day after the full "Strawberry Moon" rose in the sky, according to the Earth Observatory. (June's full moon is nicknamed the Strawberry Moon because it coincides with the strawberry harvesting season in the Northern Hemisphere, not because of its color.)

The tidal range is greatest when there is a full moon because the sun and the moon are aligned in a straight line, so they gravitationally push and pull Earth's oceans in sync. This is known as a "spring tide," but it happens throughout the year.

In addition to having a significant tidal range, the Rokan River is home to a regular tidal bore — a powerful surge of water that rushes upstream like a giant wave during high tides. This rare phenomenon occurs only in estuaries with a narrow mouth and a high tidal range.

A 2022 study revealed that the surge is responsible for transporting large amounts of sediment back up the river. If a bore occurred before the satellite photo was taken (which may or may not have happened), it could have stirred up some of the sediment streaks visible in the image.

All of this tidal action can have a significant impact on the estuary itself. A 2016 study compared satellite images of the estuary between 2000 and 2014, and found that the shoreline along the north of Halang Island (which clearly extends beyond the small landmass in the image) is growing at an average rate of 220 feet (67 m) per year.

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This dazzling satellite photo shows a glowing ring of plankton surrounding a remote group of New Zealand islands. The illuminated landmasses are hotspots for deadly whale stranding events, which are tied to the same underwater structure that birthed this spectacular bloom.

The gleaming ring encircles the Chatham Islands — a group of 10 islands in the Pacific Ocean around 520 miles (840 kilometers) west of Christchurch, on the east coast of New Zealand's South Island. The largest of those islands, Chatham Island and Pitt Island, are approximately 36 miles (58 km) and 9 miles (15 km) across, respectively. (The other landmasses are much smaller and are not clearly visible in the image.)

The Chatham Islands are surrounded by the Chatham Rise — a shallow underwater plateau that extends up to 900 miles (1,450 km) from the South Island's east coast. This hidden structure acts like a giant ramp that funnels cold, nutrient-rich waters to the ocean's surface. In the summer, warmer seasonal currents mix with this nutrient-rich water, providing the perfect conditions for algae to bloom.

The circular bloom in the photo was one of the largest in recent decades. It consists mostly of coccolithophores, a group of photosynthetic plankton, or "phytoplankton," that convert sunlight into energy and surround themselves with intricate calcium carbonate armor.

The satellite image was captured with a special near-infrared filter, which likely enhanced the algae's vivid hues. However, the blooming microorganisms would have been clearly visible to the naked eye from space, according to NASA's Earth Observatory.

Phytoplankton are the base of the pelagic (open-water) food web, similar to plants' role in terrestrial environments. As a result, the Chatham Islands are marine biodiversity hotspots that are home to various animals, including penguins, albatrosses, seals and sea lions, as well as commercially important populations of cod and lobsters.

At least 25 species of whales and dolphins, or cetaceans, are also drawn to the islands to feed, including orcas (Orcinus orca), sperm whales (Physeter macrocephalus) and pilot whales (Globicephala), according to New Zealand's Department of Conservation (DOC). However, this is not always a good thing for the visitors.

Large groups of cetaceans often get disoriented in the shallow waters and can end up accidentally swimming too close to shore and getting trapped as the tide goes out, which is often fatal without human intervention.

Chatham Island has experienced multiple strandings over the past few years, including an event in October 2022 when nearly 500 pilot whales were euthanized on Chatham Island after washing up over the space of around four days, according to a DOC report. In 1918, more than 1,000 pilot whales are also believed to have died there after washing ashore, which remains the most deadly whale stranding event in recorded history. (Pilot whales are particularly prone to stranding because they are highly social, so an entire pod can be dragged into danger by a single injured or disoriented individual.)

Cetaceans are not the only creatures that have met an untimely end on the Chatham Islands. The archipelago was previously home to at least eight endemic bird species that have since gone extinct, including the Chatham penguin (Eudyptes warhami). Most of these species disappeared between 150 and 200 years ago due to the island's first human settlers, who arrived there from Polynesia in the 15th century.

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This striking satellite photo shows the point where a tiny lake bisects the snowy rim of a massive ancient glacier on a Canadian island in the Arctic Circle.

The small body of water, dubbed Gee Lake, is around 2 miles (3.2 kilometers) across at its widest point. It is located along the edge of the southeast limb of the Barnes Ice Cap — a roughly 2,300-square-mile (6,000 square kilometers), "bowling-pin-shaped" glacier situated at the center of Baffin Island in Canada's Nunavut territory.

In this image, captured in early September 2010, both the lake and the ice cap are still snow-free, except for the ice cap's edge, due to warmer summer temperatures. As a result, we can see the dark gray of the glacier, which is caused by the buildup of dust between layers of ice "spanning time periods that dwarf a human life," according to NASA's Earth Observatory. (In the winter, the glacier, lake and surrounding landscape are blanketed with snow.)

The exposed ice, which is up to 1,600 feet (500 meters) thick, is marked with striations that look like the "growth lines on a clamshell" running east to west, Earth Observatory representatives wrote.

These grooves are ridges cut by meltwater streams running off the glacier, Ted Scambos, a glaciologist at the University of Colorado Boulder and the National Snow and Ice Data Center, told the Earth Observatory. And while they give the impression that the ice is undulating, the surface of the glacier is surprisingly flat and smooth, he added.

Ice core samples collected from the glacier reveal that parts of the Barnes Ice Cap date back around 20,000 years, making it Canada's oldest known ice, according to a 2008 study. It is also the last remaining fragment of the Laurentide Ice Sheet, which covered most of Canada and the northern U.S. as far back as 100,000 years ago and helped to carve out the Great Lakes.

By around 20,000 years ago, as the last ice age began to thaw, most of the Laurentide Ice Sheet had melted away. But what was left slowly migrated north, toward what is now Baffin Island, where it eventually disappeared into the sea (aside from the Barnes Ice Cap). A 2009 study revealed that most of the melting ice passed through the Kangiqtualuk Uqquqti Fjord (previously known as the Sam Ford Fjord), around 70 miles (110 km) northeast of Gee Lake.

Although most of the Laurentide Ice Sheet is long gone, we can still see its impacts today. Recent research has shown that its meltwater has significantly altered ocean currents, while the geological "rebound" caused by the vanished weight that once pressed down on North America may be causing some major U.S. cities to sink and also affecting parts of Greenland.

Like most other glaciers in the Arctic and Antarctica, the Barnes Ice Cap is shrinking as a result of rising temperatures from human-caused climate change.

Although its current rate of ice loss is minimal — just a few meters of retreat per year — this will increase sharply as temperatures rise further. A 2017 study predicts that most of the glacier will "likely disappear in the next 300 years."

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This striking satellite snap shows a verdant mass of algae and other aquatic plants sprawling across the surface of a recreational reservoir in South Africa. This frequent phenomenon releases toxic chemicals into the water and gives rise to hidden "dead zones" that can cause widespread fish fatalities.

The reservoir is located at the Hartbeespoort Dam, which was constructed in the 1920s around 25 miles (40 kilometers) west of Pretoria. The artificial water source lies just south of the Magaliesberg mountains, which are partially visible along the top of the image, and is fed by the Crocodile River (spelled Krokodilrivier in Afrikaans), which cuts through the nearby peaks. In addition to providing fresh water to nearby cities and farms, it is used for recreational activities, including fishing and water sports.

Most large bodies of water experience seasonal blooms, where photosynthetic algae, or cyanobacteria, rapidly multiply and spread across their surfaces due to changes in weather or nutrient inflow. However, the Hartbeespoort reservoir is in a constant state of "hypereutrophication," which means it has an overabundance of nutrients, such as nitrogen and phosphorus. As a result, the blooms there are much more frequent and intense, according to NASA's Earth Observatory.

"On clear days … satellite images often reveal a reservoir with shades of deep blue interrupted by drifting patches of vivid green," Earth Observatory representatives wrote.

However, it is not just algae that bloom across the reservoir's surface. The verdant masses also include aquatic plants, including water hyacinths (Pontederia crassipes) and Salvinia minima, both of which are invasive species and grow across the reservoir's surface in large, intertwined mats.

Eutrophication occurs when too many nutrients are added to a body of water, often due to human influences, and can lead to unnaturally large algal blooms. "It's like having a garden," Bridget Seegers, an oceanographer at Goddard Space Flight Center in Maryland who leads NASA's Cyanobacteria Assessment Network, told the Earth Observatory. "If you add a lot of nutrients, you're going to have a lot of growth." (Hypereutrophication is a more extreme version of this phenomenon.)

However, unlike in a garden, you cannot simply cut back the blooms you don't want, and the consequences of not being able to contain the plant life are much more severe. For example, some of the algae within the Hartbeespoort reservoir can produce toxins that must be filtered out of the water for it to be safe to drink.

However, the bigger issue is that the excessive growth of plant life on the surface sucks up the oxygen from the water below, making it toxic to fish that need to extract oxygen from water via their gills to breathe. These areas of oxygen-poor water are often dubbed "dead zones," and when the blooms spread widely, there are few safe spaces for the fish to go.

In April 2023, a lack of oxygen in part of the reservoir was linked to a mass die-off of fish, including hundreds of large carp, according to a government report. And in November 2025, another bloom likely triggered a similar die-off and left fish "gasping for air" at the reservoir's surface, according to South Africa-based News 24. These blooms eventually disappear, but the next one is rarely far behind.

The Hartbeespoort reservoir has experienced near-continuous hypereutrophication since the 1970s, excluding a brief period in the 1990s when a successful bioremediation program was introduced but then was quickly scrapped due to high costs. As a result, algae have been blooming constantly, spreading and dying across the reservoir's surface for decades.

You can see this in the animation below, which was made from aerial images collected by the Landsat 8, Landsat 9 and Sentinel satellites between June 2022 and July 2023.

A 2023 study that analyzed data from the previous four decades found that the main culprit was the Crocodile River, which has become extremely polluted with runoff from farms and golf courses that use nutrient-rich fertilizers.

In addition to threatening wildlife, the toxins in the water have been known to cause rashes on water-sports enthusiasts and sicken dogs.

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This intriguing astronaut photo shows a series of rocky rings and their distinctive "hat" towering above a dune sea in the Sahara. The concentric, shadow-filled walls are home to ancient artworks and, occasionally, herds of cattle.

The colossal structure, known as Mount Arkanu (sometimes spelled Arkenu), is a massif, or group of mountains, that stands up to 2,600 feet (800 meters) above the surrounding sands and stretches up to 15.5 miles (25 kilometers) across at its widest point. The peaks are located in southeast Libya, near the border with Egypt.

Due to the mountains' shape, scientists previously assumed that the massif was an ancient impact crater that formed when a giant space rock slammed into the northeast Sahara. But more recent research has shown that the rocky rings are not of extraterrestrial origin.

Instead, the mountains were created when "magma [repeatedly] rose toward the surface and intruded into the surrounding rock," according to NASA's Earth Observatory. This formation process likely ended hundreds of millions of years ago but has not been properly dated.

"Repeated intrusion events produced a series of overlapping rings, their centers roughly aligned toward the southwest," Earth Observatory representatives wrote. "The resulting ring complex — composed of igneous basalt and granite — is bordered to the north by a hat-shaped formation made of sandstone, limestone, and quartz layers."

The massif has two large gaps in its outermost southern wall (bottom right in the photo). These have been slowly carved out by a pair of wadis, or ghost rivers, which sporadically fill with water when it rains. The phantom waterways can also be seen snaking through the dark plateau surrounding the complex.

This region of the Sahara is hyperarid; it gets only 1 to 5 millimeters (0.04 to 0.2 inches) of rain each year, according to the Earth Observatory. However, the massif receives between 5 and 10 mm (0.2 to 0.4 inches) of rain annually, due to a phenomenon known as "orographic precipitation," which occurs when clouds form over raised landforms, according to the U.K. Met Office.

As a result of this additional water, the rings are partially filled with grasses, bushes and trees that the shadows from the towering peaks shelter from the desert's scorching temperatures.

Cattle herding

The combination of shade, vegetation and occasional water has historically made the massif a popular destination for nomads traversing the surrounding dune seas.

Another massif, Mount Awaynat (sometimes spelled Uwaynat or Uweinat), is located roughly 12 miles (20 km) southeast and has provided similar benefits to desert wanderers for generations.

Some of the canyon-like walls of both Mount Arkanu and Mount Awaynat are covered with rock carvings, or petroglyphs, that were first discovered in 2003. These ancient artworks depict human fugures, along with cattle and other tethered animals, such as giraffes.

Early-20th-century explorers noted that members of the local bedouin tribe trekked their cattle herds to the massifs and left them inside to graze for up to three months at a time — and blocked up the holes created by the wadis to stop the animals from wandering off.

The cattle carvings within both structures suggest that this practice has been going on for thousands of years.

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This striking satellite photo shows a bright plume of swirling marine mud that was whipped up off the coast of Florida following a blast of cold air from the Arctic, which brought severe winter weather to large parts of the U.S. earlier this year.

In late January, an extreme cold front descended across the eastern half of North America as the polar vortex — the ring of cold air that circles in the atmosphere above the Arctic — stretched southward, just as it did approximately a year previously.

This phenomenon, known as an Arctic blast, brought temperatures as low as minus 43 degrees Fahrenheit (minus 42 degrees Celsius) to parts of the Midwest, according to the National Weather Service's Weather Prediction Center. It also sparked fears that trees might start exploding.

In addition to dumping snow as far south as Georgia, this weather front also helped create a giant underwater plume in the West Florida Shelf — a large area of shallow water created by a submerged continental shelf that extends off Florida's southwest coast.

The plume, which consists mostly of calcium carbonate scattered across the seafloor, stretched up to 150 miles (240 kilometers) from the coast at its widest point, which extended outward from Key West (partly visible as three large landmasses in the right of the photo), according to NASA's Earth Observatory. It also stretched around the same distance from north to south (beyond the upper border of the photo).

Calcium carbonate (CaCO₃) is an inorganic chemical compound. While it is commonly found in rocks, such as limestone, the swirls in the photo are made of biological CaCO₃ — created by corals, algae and crustaceans — that builds up on the seafloor as the creatures die and fall to the ocean floor. The West Florida Shelf collects high levels of this material due to its shallow waters and is often described as a "carbonate ramp" as a result.

When the cold Arctic air descended on North America, it triggered strong winds across the shelf's surface, which created currents that dragged the calcium carbonate and other seafloor sediments closer to the surface, James Acker, a chemical oceanographer at the University of South Florida and NASA's Goddard Earth Sciences Data and Information Services Center, told the Earth Observatory.

Similar plumes have appeared in this area after hurricanes, which can also whip up seafloor sediments. However, such plumes are often less intricate than the one in this image because the disturbance to the ocean floor is much more violent.

Recent research has suggested that Arctic blasts like the one that painted this plume could become more common in the future as a result of human-caused climate change, which has made it more likely that the polar vortex will stretch southward. Therefore, we may see many more seascapes like this in the coming decades.

Hidden details

The plume is most highly concentrated in a line stretching directly between Key West and Dry Tortugas National Park, which comprises seven small islands (visible in the left of the photos).

Faint sediment swirls can also be seen farther from the coast. They include a rare pair of counter-rotating eddies, also called a "hammerhead eddy" (visible in the upper left of the image), which was created when the cold waters of the plume collided with the warmer waters in the Gulf of Mexico, according to the Earth Observatory.

This swirling sediment is also partly tied to the cold weather. "The cold air cools off the shallow water on the banks and makes it denser than the surrounding warmer open ocean water," Acker said. When this dense water sinks and flows offshore with the tides, it can carry some of the sediment toward the shelf’s edge, he added.

In the opposite direction, a thin trail of sediment can be seen snaking beneath the plume and terminating in a distinctive curl. This "loop current" formed when sediment-filled water spurted into the deeper waters of the Atlantic Ocean through hidden channels in the shelf's floor.

The last time such a visible loop current was seen in this area was in the aftermath of Hurricane Ian, which bashed into Florida in 2022 after pummeling Cuba, according to the Earth Observatory.

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This intriguing astronaut photo shows off the contrasting colors of five ephemeral lakes that emerged around the edges of a giant salt pan after a major flooding event in southwest Africa.

The kaleidoscopic scene occurred in the northwest corner of the Etosha Pan — Africa's largest salt flat, or mineral pan, which covers around 1,800 square miles (4,730 square kilometers) in northern Namibia. The name Etosha roughly translates to "Great White Place" in an Indigenous Namibian language, and the ghostly expanse is located roughly 250 miles (400 kilometers) from the country's capital, Windhoek.

The satellite photo shows a snaking pair of ephemeral rivers that drain into the Etosha Pan: the Ekuma River (left) and the Oshigambo River (right). These winding waterways are surrounded by roughly a dozen bowl-like depressions that occasionally fill with water when the rivers sporadically flood their banks.

When the image was taken, both rivers had recently flooded due to heavy rains in the region, causing around half of these pale depressions to fill with water. The rest of the lakes remained empty and are the same pale hue as the rest of the Etosha Pan.

The contrasting colors of the newly filled lakes — which include yellow, green, brown, red and pink — are likely the result of different species of algae that bloomed within their shallow waters, according to NASA's Earth Observatory. (For scale, the green lake is around 4 miles (6.5 km) long at its widest point.)

The Etosha Pan likely formed around 10 million years ago and has been a freshwater lake for most of that time. But around 16,000 years ago, toward the end of the last ice age, tectonic activity diverted one of the major rivers that fed into the lake, causing it to dry out.

As the water slowly evaporated, it left behind a thick layer of minerals, which covered the lake bed. Most of the pan's surface is covered by honeycomb-like hexagonal structures that are common among salt flats across the globe.

During flooding events, a thin layer of water can briefly lie within the pan, transforming it back into a shallow lake. However, this rarely happens, even when its rivers flood.

The last time a majority of the pan flooded was in 2006, which was also captured from space by ISS astronauts.

Wildlife haven

Despite the Etosha Pan's extreme dryness and salinity, which make it largely inhospitable to life, the area surrounding the ancient lake is covered with rich grassland and woodland.

This diverse ecosystem is protected as part of Etosha National Park, which covers 8,900 square miles (23,000 square km), and is home to a variety of animals, including lions, giraffes, zebras, hyenas, impalas, elephants, rhinos, springboks, wildebeests and ostriches, according to iNaturalist.

The salt flats themselves are also an important breeding site for flamingos, and up to 1 million of the pink birds congregate there at a time, according to the Etosha National Park website.

If you look closely at the astronaut photo, you can see the park's northern fence running across the image from left to right — just above the green lake and bisecting the red and pink lakes. This 10-foot-tall (3 meters) barrier stops the park's animals from wandering outside the woodlands where they could be targeted by poachers, according to the Earth Observatory.

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This striking satellite snap shows a massive letter Y lurking in the heart of a recently transformed Chinese desert. The unusual shape is made up of a rocky ridge and a winding, gemstone-filled river and is also home to an important eighth-century fort.

The intersecting lines are located in the middle of the Taklamakan Desert (also spelled Taklimakan and Takla Makan), which covers an area of 130,000 square miles (337,000 square kilometers) in the Tarim Basin of China's Xinjiang region.

The desert was previously considered a "biological void" — meaning it was almost completely devoid of life — due to its high temperatures and aridity. However, an ecological engineering project known as the Great Green Wall has planted more than 66 billion trees along the desert's northern edge since 1974, which has transformed it into a carbon sink that soaks up large amounts of carbon dioxide, recent research revealed.

The Y shape comprises two parts: the Hotan River, which stretches about 180 miles (290 kilometers) across the desert from south to north; and Marzatagh, a "wall-like" mountain ridge that stands around 600 feet (180 meters) above the surrounding sands and extends up to 90 miles (145 km) to the northwest, according to NASA's Earth Observatory.

The Hotan River (sometimes called the Khotan River) is fed by glacial meltwater from the Kunlun Mountains south of Taklamakan and appears green due to vegetation that grows between its braided streams. Its waters are rich in both white and green nephrite, which are prized types of jade.

Marztagh is split into seams of reddish iron-rich rocks and paler sandstone, earning it the name Hongbaishan, meaning "red-white mountain" in Chinese. It also acts as a natural barrier for sand that gets blown against the rocky wall, creating a sea of rippling, crescent-shaped "barchan" dunes along its northern edge.

The confluence of drinking water, valuable gemstones and shelter from the elements made this location an important stop on the Silk Road — a massive network of trade routes running from east to west across Asia from the second century to the fifteenth century.

The point where the two features meet is home to the crumbled remains of a military fort, which likely dates to the eighth century.

Crumbling fort

The fortification, dubbed Mazar Tagh, was built on a hill at the intersection of the Y shape by the Tibetan Empire, which existed between A.D. 618 and 842 and covered most of the Tibetan Plateau, including parts of modern-day China, India and Afghanistan.

The site was first excavated in 1907 by Hungarian-British archaeologist Aurel Stein, who uncovered more than 1,500 document fragments, transcribed on both wood and paper, according to the The International Dunhuang Programme. These texts were written in multiple languages — including Khotanese, Uyghur and Sogdian — and document the soldiers' experiences.

Other artifacts — including arrows, sheathes, shoes, dice, a comb and a pen — were also found at the site and are currently stored at the British Museum. However, the most impressive find was arguably a portrait of a "begging monk" painted on a wooden board, likely by a soldier. The monk was probably on a pilgrimage to an ancient Buddhist shrine that was built on the same hill.

Today, the hill is also home to an Islamic shrine.

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This striking satellite photo shows off the contrasting colors at the point where three rivers converge in Guyana. The multicolor waterways result from the country's unique geology, as well as an increasingly disruptive human-caused factor.

In the Indigenous Arawak language, Guyana means "land of many waters," which is an apt name, given that the country is home to 10 major rivers and dozens of smaller waterways, despite being around the size of South Carolina, according to NASA's Earth Observatory.

This unique hydrology is linked to the Guiana Shield, a 1.7 billion-year-old geologic feature that covers Guyana as well as parts of Venezuela, Brazil, Suriname and French Guiana. The shield contains hard crystalline bedrock made up of rocks such as gneiss and granite, meaning it does not easily erode except from flowing water, which has carved out many routes through the region.

In this photo, two smaller rivers — the Cuyuni River (left) and the Mazaruni River (center left) — come together shortly before merging with the Essequibo River (center right) to form one of Guyana's largest waterways.

The town of Bartica, which is home to around 15,000 people, is located on the piece of land that juts into the water at the point of the secondary merger. From there, the enlarged Essequibo River flows northward for around 30 miles (50 kilometers), before draining into the Atlantic Ocean.

Prior to merging, the Mazaruni and Essequibo are dark brown, which is likely the result of tannins — chemicals released by rotting vegetation that stain waterways via a process similar to tea brewing. The Cuyuni is light brown due to high levels of suspended sediment in its water, according to the Earth Observatory.

When the rivers meet, the lighter and darker waters do not readily mix because of the differences in density caused by varying levels of sediment.

While the presence of tannins is a natural phenomenon triggered by flooding, the high levels of sediment are the result of mining waste that is dumped in the Mazaruni.

"This image is from a wet time of year when all three rivers were running high and carrying a lot of sediment," Evan Dethier, a hydrologist at Colby College in Maine, told the Earth Observatory. "But the Cuyuni is the clear outlier, which we can attribute to the intensity of mining upstream."

Guyana is a hotspot for mining, largely because of its vast deposits of gold, diamonds and bauxite, as well as lithium, copper and nickel, which are also linked to the Guiana Shield, according to the U.S. Department of Commerce.

The country's mining industry began in ernest in the mid-2000s, and since then, the concentration of sediment in the Cuyuni has likely increased tenfold, Dethier said. Similar changes have been documented in rivers across the planet.

A 2022 study led by Dethier revealed that sediment concendrations in rivers in the Southern Hemisphere has risen by around 40%, largely due to mining and deforestation. However, the opposite is true in the Northern Hemisphere due to the construction of large-scale dams, which have blocked sediment flow by around half.

The changes in global sediment flow also may be affecting the marine environment, because the sediment input in most of the world's oceans has changed drastically, the study warned ‪—‬ but it is still too soon to see what sort of long-term effect this may have.

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This striking satellite photo shows a recently uncovered meteor crater in China that is likely the youngest impact structure on Earth and the largest in its wider age bracket. The horseshoe-shaped depression is also only the second impact crater ever discovered in the country.

The Yilan crater is an incomplete, nearly circular impact crater located in the Lesser Xing'an (also spelled Khingan) mountain range of China's Heilongjiang province, around 12.5 miles (20 kilometers) northwest of the town of Yilan. It is approximately 1.15 miles (1.85 km) across at its widest point, and its ringed walls reach up to 500 feet (150 meters) above the crater floor.

Chinese researchers discovered that the incomplete ring was an impact crater in mid-2021, around three months before this photo was taken. Until then, it had largely gone unnoticed because it is surrounded by thick forests. Although locals knew about the structure, they called it Quanshan, meaning "circular mountain ridge," which suggests they had no idea of its extraterrestrial origins.

However, when the research team dug up to 1,440 feet (440 m) beneath the crater's floor, they found "shocked quartz, melted granite, glass containing holes formed by gas bubbles, and tear-drop-shaped glass fragments" — all clear signs that a sizable space rock had slammed down there, according to NASA's Earth Observatory.

Carbon dating revealed that the crater formed sometime between 46,000 and 53,000 years ago, meaning it could be the youngest of the roughly 200 major impact craters on Earth.

Until this discovery, the most widely accepted "youngest major crater" on Earth was Barringer Crater (also known as Meteor Crater) in Arizona, which dates back 50,000 years, according to the Lunar and Planetary Institute. Given the uncertainty around the Yilan crater's age, researchers cannot be sure that it is younger than Barringer Crater, although it is thought likely.

The Yilan crater is also the largest of any impact crater under 100,000 years old, so it beats another record previously held by Barringer Crater, which is around 0.75 mile (1.2 km) across.

As you can see in the satellite photo, the southern third of the crater's rim is missing. Researchers are unsure exactly when or how this section of the crater's rim disappeared. However, sediment found on the crater's floor hints that there was formerly a lake within the crater, which strongly suggests that the structure was once fully intact, according to the Earth Observatory.

Chinese craters

The Yilan crater is the first impact crater to be discovered in China since the 1.1-mile-wide (1.8 km) Xiuyan crater in Liaoning province, which dates back to between 330,000 and 1.1 million years ago, was confirmed in 2009.

Given how large China is — around the same size as the U.S. by land area — it has long been a mystery as to why more impact craters haven't been found there. However, others have been uncovered following the discovery of the Yilan crater.

In September 2023, scientists discovered a third Chinese crater, around the same size as the Yilan crater. Carved into the summit of a mountain near the North Korean border, the crater dates back at least 150 million years.

Then, in October 2025, scientists confirmed a fourth impact structure, dubbed the Jinlin crater, on a mountain near Zhaoqing in China's Guangdong province. This crater is only around 3,000 feet (900 m) wide and may date to as recently as the current epoch, known as the Holocene, which began 11,700 years ago, according to Sci News, although its age is unconfirmed.

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This intriguing astronaut photo reveals the hidden beauty of the expansive Great Dyke of Zimbabwe, a massive seam of ancient magmatic rock that's chock-full of valuable minerals.

The Great Dyke stretches approximately 342 miles (550 kilometers) across central Zimbabwe, from outside the capital city, Harare, in the northeast, to near the country's second-largest city, Bulawayo, in the southwest. It ranges from 2 to 8 miles (3 to 13 km) wide and contains hills that rise up to 1,500 feet (450 meters) above the surrounding plateaus, according to NASA's Earth Observatory.

Despite its name, the gigantic structure is not actually a dike — a vertical sheet of frozen magma that cuts through existing rock layers. Instead, it is a lopolith, which is similar to a dike but forms parallel to existing rock sheets and is both flatter and more lenticular, or saucer-shaped.

The Great Dyke is thought to be the longest continuous igneous intrusion, or structure of elevated magmatic rock, anywhere on Earth, according to the Zimbabwe Geological Survey.

The astronaut's snap shows the southernmost tip of the structure, around 78 miles (125 km) from Bulawayo. In 1983, astronauts on board the space shuttle Challenger also captured a striking photo of the structure's southern half, and in 2003, NASA's Terra satellite imaged the lopolith's entire length (see below).

Geologists think the lopolith formed around 2.5 billion years ago, when magma from Earth's mantle gradually seeped upward through tectonic plate faults. This means the structure has existed for more than half of Earth's roughly 4.5 billion-year history.

This magma was full of valuable minerals that are normally locked deep below Earth's crust, which has made the area a hotspot for mining. Today, there are at least half a dozen major mines along the lopolith's length, according to Mining Zimbabwe magazine.

The Great Dyke is full of important metals, including gold, nickel, copper, titanium, iron, vanadium and tin, according to the Earth Observatory.

However, it is best known for its expansive platinum deposits, which are collectively the third largest of their kind on Earth, as well as its unusually pure chromite, which contains high levels of chromium — a key component in the production of stainless steel, according to Mining Zimbabwe.

The Great Dyke is also rich in rocks that are used for sculpting, "resulting in an artist's paradise akin to the Greek marble quarries," local artist Michael Nyakusvora wrote on their website.

"The Great Dyke of Zimbabwe is more than a line on a map — it's a lifeline of economic opportunity [and] a geological marvel," according to Mining Zimbabwe.

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This amorous astronaut snap, first released by NASA on Valentine's Day 2025, highlights a pink, heart-shaped salt lake in Argentina.

Salinas Las Barrancas, sometimes known as Laguna de Salinas Chicas, is a shallow salt lake in the lowland plains of Argentina's Buenos Aires province, roughly 33 miles (53 kilometers) west of the port city of Bahía Blanca.

The lake bed is around 6 miles (10 km) across at its widest point and regularly fills with water after heavy rainfall. However, this liquid quickly evaporates due to the region's intense sunlight, exposing crystal-rich salt flats that are mined by local people, according to NASA's Earth Observatory.

In this photo, the lake appears to be close to empty because of its lighter-pink hue, which is most likely the result of an imbalance between Dunaliella salina — a species of dark-red algae that thrives in most of Earth's salt lakes — and other microorganisms in the water, according to a 2022 Smithsonian magazine article about similarly colored salt lakes.

"We have rainy seasons, when the salinity levels decrease [because there's more water in the ponds]. When there's less salt, the Dunaliella survives and the ponds look brownish-red," Lilliam Casillas Martinez, a microbiologist at the University of Puerto Rico at Humacao, told Smithsonian magazine while explaining the colors of similar salt ponds in Puerto Rico. "During the dry season, it gets really salty. The Dunaliella dies and the archaea and bacteria take over. Then it becomes pink, pink, pink."

Locals mine up to 330,000 U.S. tons (300,000 metric tons) of salt from the flats of Salinas Las Barrancas twice a year, between the region's rainy seasons, according to a 2019 feature on the lake by Argentine news site La Nación. Most of this salt is replenished by the next major rainfall, and experts predict that mining will remain viable there for 5,000 years.

Mining is largely carried out using traditional processes, including scraping salt from the flats' surface with handheld tools. Workers must take precautions to protect their eyes and skin from intense sunlight that reflects off the pure white crystals. "The salt becomes part of your life," local worker Chepo told La Nación (translated from Spanish). "For someone else, it's a hellish place, but for me, the salt flats are my home; you get used to not being able to see."

Salinas Las Barrancas' high salinity means that not much can survive there. However, some salt-resistant vegetation does grow around the lake's edges, according to the Earth Observatory.

It is also home to colorful birds, including vibrant yellow cardinals (Gubernatrix cristata) and bright-pink Chilean flamingos (Phoenicopterus chilensis). These birds feed on tiny crustaceans that are rich in carotenoids — organic pigments synthesized by plants, algae and bacteria.

These specific carotenoids come from the Dunaliella algae, which the tiny crustaceans feed on, and naturally produce both red and yellow pigments. Without these pigments in their diets from birth, both bird species would be different colors; yellow cardinals are naturally red, while flamingos are born grayish-white.

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This trippy satellite snap shows the hidden intricacies of the biomass, or carbon-rich material, surrounding a winding river in Bolivia. The first-of-its-kind image, snapped last year, shows the unique orbital perspective from one of Europe's newest spacecraft.

The striking photo shows a section of land — around 56 miles (90 kilometers) long and 37 (60 km) wide — surrounding the Beni River (or Rio Beni) in northern Bolivia. The convoluted waterway stretches approximately 680 miles (1,095 km) from its origin in the Andes, just north of La Paz, and into Brazil, where it merges with the Amazon River.

The image was snapped by the European Space Agency's (ESA) Biomass satellite, which launched April 29, 2025. This satellite scans Earth's surface using polarized radar, allowing it to detect subtle differences in biomass across the landscape.

In the image, rainforests appear green, grasslands are purple, wetlands are reddish, and the river and nearby lakes appear black. (The photo has also been flipped so that north is to the right of the photo.)

The mission's "first images are nothing short of spectacular — and they're only a mere glimpse of what is still to come," Michael Fehringer, an ESA scientist and Biomass project manager, said in a statement when the image was released.

One key goal of the Biomass satellite is to measure how Earth's carbon-rich areas are shifting in response to human pressures, such as climate change and deforestation.

For example, Bolivia is among the countries hit hardest by deforestation. But it is hard to quantify the scale of this issue using normal satellite photos, where forests, grasslands and wetlands appear to merge (see above).

ESA has since revealed several more stunning images from the Biomass satellite, including snaps of Mount Gamkonora in Indonesia, the Ivindo River in Gabon, the Tibesti Mountains in Chad and the Nimrod Glacier in Antarctica.

The satellite is now fully online and will scan the entirety of Earth's forests every six months.

Biomass's radar technology will also be particularly good at penetrating and assessing ice masses, which will be an important secondary goal of the spacecraft's mission.

On Jan. 26, ESA announced that it is opening up the satellite's dataset to the public, which will allow for more research. This collaborative approach will "unlock vital insights into carbon storage, climate change, and the health of our planet's precious forest ecosystems," Simonetta Cheli, ESA's director of Earth observation programs, said in the statement.

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This intriguing astronaut photo shows an oasis town and crop circles lurking within the shadowy tail of a "camel-hump" mountain in the harsh Saudi Arabian desert. The unlikely settlement lies within an ancient lake bed and is home to rock art dating back thousands of years.

The town, known as Jubbah, is located around 415 miles (670 kilometers) northwest of Riyadh and is home to around 5,000 people. It lies at the heart of the hyperarid Nafud (also spelled Nefud) desert, but it has remained an agricultural hot spot for generations thanks to its plentiful supply of underground water. Today, most farming is focused around center-pivot irrigation, which creates circular fields of vegetation.

Jubbah sits within a bowl-like depression left over from an ancient lake, or paleolake, that measures around 12.5 miles (20 km) long and 2.5 miles (4 km) wide. As a result, parts of the town lie "hundreds of feet" below the surrounding sea of dunes, according to NASA's Earth Observatory.

At the western end of the paleolake stands a 4,144-foot-tall (1,264 meters) mountain, dubbed Jabal Umm Sinman (meaning "two camel-hump mountain"), due to "its resemblance to a camel with two humps resting on the ground" when viewed from ground level, according to Visit Saudi.

The prevailing winds in the area blow from west to east (left to right in the image), meaning Jabal Umm Sinman generates a "wind shadow" that largely shields Jubbah from sand being blown across the desert, according to the Earth Observatory.

Before the desertification of the Arabian Peninsula, Jubbah Lake was one of several freshwater sources in the region. Most of these sites had dried up by around 5,000 years ago. However, Jubbah Lake likely persisted longer thanks to its subsurface aquifer, which continues to supply the town's water.

This likely made the lake a popular landmark for prehistoric humans wandering through the desert, long before the town was established. If you look closely at the image, you can see a faint road (above Jubbah), which likely matches the path used by these early travelers, according to the Earth Observatory.

These people also left their mark in the foothills surrounding Jabal Umm Sinman by carving symbols and pictures in the rocks. In total, there are around 5,500 inscriptions and 2,000 animal depictions, including portrayals of ibex, leopards, ostriches, dogs on leashes, and more than 1,000 camels.

This extensive rock art dates back at least 10,000 years and is part of a UNESCO World Heritage Site, along with two other nearby sites near Shuwaymis.

Saudi Arabia is an archaeological hot spot for rock art and other Paleolithic structures. For example, Jubbah is around 155 miles (250 km) northeast of the famous Al Naslaa rock — a hefty sandstone slab covered in prehistoric carvings and mysteriously split into two perfect halves.

Recent research into 8,000-year-old giant "kite" structures in the region hints that the carvings may be the world's oldest megastructure blueprints.

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This striking satellite snap highlights the immense power of 7-story waves crashing along the Portuguese coast and ejecting massive sediment plumes under the sea. The same day this photo was taken, a local 18-year-old surfer set a new world record by riding one of the colossal crests.

The Landsat 8 satellite captured this epic scene near the town of Nazaré in western Portugal, a region famous for having some of the tallest waves on Earth. Nazaré is home to around 15,000 people and regularly hosts "big-wave" surfing competitions, which attract surfers from around the world. The swells there are so big that surfers often have to be towed into the breaking waves with a jet ski.

The monster waves in the image likely reached heights of around 80 feet (24 meters), which is roughly equivalent to a 7-story building. This is exceptionally tall — even for Nazaré, where waves usually peak up to 50 feet (15m) at this time of year — and would usually be considered too dangerous to surf.

As these waves broke along the shore, their powerful undercurrents ripped up sand and other sediments from the seafloor and spat them out in the opposite direction to the waves, creating murky underwater clouds that could be seen from space.

The plumes in this photo extend up to 6 miles (10 kilometers) from the coastline, according to NASA's Earth Observatory.

Later the same day, local surfer António Laureano rode an even loftier wave, estimated to be approximately 101.4 feet (30.9 m) tall — the largest wave ever surfed by a human.

This record is not officially recognized by the World Surf League (WSL) because the organization's representatives did not calculate the wave's height. Instead, the height was determined by oceanographers at the University of Lisbon, who analyzed a video of the wave sent to them by Laureano, surfing news site Surfer Today reported at the time.

The current WSL record for the tallest wave ever surfed belongs to German surfer Sebastian Steudtner, who rode a 93.7-foot (28.6 m) wave, also at Nazaré, on Feb. 24, 2024, according to Surfer.com.

In total, seven of the official top 10 largest waves ever surfed have occurred at Nazaré, according to Red Bull.

"Big-wave" hotspot

The secret behind Nazaré's giant waves is the Nazaré Canyon just southwest of the town. It is the largest submarine canyon in Europe, stretching 130 miles (210 kilometers) long and roughly 3 miles (4.8 km) deep into the Atlantic Ocean.

Water inside the canyon travels faster than shallower water, forming large waves at depth that are "bent" in the direction of Nazaré. As they approach the coast, these large waves collide with other waves coming from the northwest, which further amplifies their speed and allows them to quickly rise when they approach the shore.

Occasionally, the waves can be further amplified by strong offshore winds. This was the case with the supercharged swells in the satellite photo, which were partially fueled by the remnants of Hurricane Epsilon, according to the Earth Observatory.

Nazaré's big wave phenomenon is highly seasonal, with the largest waves typically occuring between November and February. In the summer months, the waves almost completely disappear, allowing tourists to flock back to the beaches and swim in the sea. However, even then, disaster can still strike.

In August 2012, for example, a five-year-old girl and her 66-year-old grandfather, both British nationals, were killed after being dragged out to sea by a massive "rogue wave" as they were walking on a nearby beach, according to the BBC.

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This striking satellite photo shows rippling ribbons of ethereal ice swirling like turbulent clouds on the surface of Lake Michigan, alongside a snow-covered Chicago. The wintery scene occurred during an extreme cold snap triggered by changes to the polar vortex, experts say.

The greater Chicago region is home to around 9.5 million people and is near the southernmost end of Lake Michigan — the third-largest of the Great Lakes, which covers an area of around 22,300 square miles (57,750 square kilometers) across Illinois, Indiana, Wisconsin and Michigan.

Between Jan. 19 and Jan. 24, 2025, the Windy City and other parts of the eastern U.S. were hit by an unusual cold snap, partially triggered by a sudden expansion of the polar vortex — the persistent area of cold, low-pressure air circulating high in the stratosphere above the Arctic. During this time, temperatures in Chicago fell to as low as minus 33 degrees Fahrenheit (minus 36 degrees Celsius), according to the National Oceanic and Atmospheric Administration (NOAA).

This sudden drop in temperature, coupled with strong offshore winds, caused ice to form around the coastline and be pushed outward, creating the beautiful swirls. These flowing ribbons look a lot like clouds when viewed from above, but they are entirely ice, according to NASA's Earth Observatory.

In total, around 20% of Lake Michigan was covered by ice when the satellite photo was taken, which is just above average for the time of year, according to NOAA’s Great Lakes Environmental Research Laboratory (GLERL).

While lake ice is common in January, the extent of ice on Lake Michigan doesn't normally peak until February or March. It is also more common to see uniform sheets of ice rather than the flowing patterns visible in this image.

In this case, the darker, wispy ice near the lakeshore likely accumulated into thicker offshore constructs with rough edges that appear more white when viewed from above, Jia Wang, an ice climatologist at GLERL, told the Earth Observatory.

Other Great Lakes were also impacted by the cold snap, including Lake Erie, which saw up to 80% of its surface frozen, according to GLERL. Erie's ice was so thick and emerged so quickly that a Canadian cargo freighter was trapped in place for three days, according to the New York Times.

This is not the first time that satellite photos have revealed something unusual about Lake Michigan. In 2024, aerial images helped researchers identify more than 40 mysterious craters scattered across the lake's bed, which currently have no definitive explanation.

The low temperatures and strong winds around Chicago can also cause other unusual winter sights, such as bizarre chess piece-like sand sculptures along Lake Michigan's beaches, known as "hoodoos," which form when frozen chunks of sand are exposed to strong gusts.

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This intriguing astronaut photo shows off a series of rippling sandbanks surrounding a pair of small islands in the Bahamas. The submerged swirls were partly carved out by a coral reef lurking on the edge of a hidden ocean "drop-off."

The Bahamas is made up of more than 3,000 islands and smaller cays interspersed with coral reefs, fast-flowing tidal channels and shallow underwater structures, known as sand banks. These features collectively make the islands "one of the most recognizable places on Earth for astronauts," according to NASA's Earth Observatory.

This photo shows a series of intricate sandbanks and a shallow barrier-like coral reef in the waters surrounding two diminutive islands — Carter's Cays (lower left) and Strangers Cay (upper right). The islands are two of the northernmost landmasses in the Bahamas, located around 125 miles (200 kilometers) east of Florida. (For context, Strangers Cay is around 2.2 miles (3.6 km) across at its widest point.)

The sand banks, which can be seen winding in and around the two cays like ribbons, have been sculpted by decades of unchanged ocean currents, causing sand to pile up in the same place over time.

But the coral reef — which cuts across the bottom right corner of the image and has waves breaking across its far edge — is much older, having likely built up over several millennia.

The largest and most prominent sandbank, which looks like a giant U-shape in the center of the image, lies directly opposite a large gap in the coral reef. This is no coincidence: The break in the reef has created a strong and sustained tidal flow that has pushed the sand much further backward, according to the Earth Observatory.

These sand swirls are fairly small compared with some of the larger sandbanks in the region. The biggest is the Great Bahama Bank, which covers an area of around 80,000 square miles (210,000 square kilometers) off the Exuma Islands in the central Bahamas and supports a massive seagrass ecosystem.

These features frequently draw comparisons to abstract paintings or the Northern Lights, due to their shape and captivating glow, when viewed from above. However, their supposed luminosity is actually just an optical illusion caused by their proximity to the ocean's surface. In some areas, the sand is likely only around 6.5 feet (2 meters) below the waves, according to the Earth Observatory.

If you look closely at the ocean's surface in the image, you will also notice that the water to the upper left of the islands is very light and covered with shimmering streaks, while the bottom right corner of the image — beyond the reef — is darker and exhibits traditional wave patterns.

This is the result of a steep drop-off in the deep ocean just beyond the coral reef, similar to the one depicted in the film "Finding Nemo." Beyond this point, ocean currents create the swells that many people see from the window of an airplane. But behind the reef, the wind sculpts the ocean's surface into subtle streaks instead.

This drop-off is also why there are no sandbanks visible beyond the reef.

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This incredible astronaut photo shows the unusual point where a hefty non-retreating glacier, a pristine turquoise lake and a murky green "river" perfectly converge at the intersection of three valleys in Argentina.

The trio of hydrological features — the Perito Moreno Glacier, Lago Argentino and Brazo Rico — lie at the heart of Los Glaciares National Park, which covers an area of around 2,300 square miles (6,000 square kilometers) in the Santa Cruz province of southern Argentina, near the country's border with Chile.

The aerial photo doesn’t just show off these three aqueous entities in a single frame; if you look closely, it also reveals the point where the trio touch in a slim channel along the western edge of the Magallanes Peninsula — the rocky outcrop that lies between the lake and the river, according to NASA's Earth Observatory.

In this photo, the waters of Lago Argentino and Brazo Rico are likely in direct contact with each other (as in the photo below). But their waters do not readily mix because they have different densities, due to their respective concentrations of suspended particulate matter, according to a 2022 study.

But every four to five years, the glacier's tongue juts forward, colliding with the Magallanes Peninsula and temporarily damming the Brazo Rico. When this happens, the surface of the murky body of water rises by up to 100 feet (30 meters) until a pressure build-up causes the icy dam to spectacularly "rupture," the Earth Observatory previously reported.

Perito Moreno is the largest glacier in Patagonia, which includes parts of Argentina and Chile. It is approximately 19 miles (30 km) long with ice up to 200 feet (60 m) thick. In total, the glacier holds roughly the same amount of water as 360,000 Olympic swimming pools, according to back-of-the-envelope calculations.

The glacier is "non-retreating," meaning that it is not shrinking despite rising atmospheric temperatures triggered by human-caused climate change. This is extremely rare nowadays, and Perito Moreno is frequently cited as one of the "world's last major non-retreating glaciers." However, a recent study hints that it may finally be starting to shrink.

Lago Argentino is the largest freshwater lake in Argentina, covering a total area of around 550 square miles (1,425 square km). The section visible in the astronaut photo is the lake's southernmost arm. It contains glacial meltwater filled with rocky particles released by the glaciers' constant movements, collectively known as "glacier milk," which gives the water its striking turquoise color.

The lake's northernmost arm also connects to the Upsala Glacier, which is currently in full retreat.

Brazo Rico, meaning "rich arm" in Spanish, is also technically part of Lago Argentino. However, it has become increasingly isolated from the rest of the lake due to repeated damming by the Perito Moreno glacier, making it behave more like a river than part of a lake.

The frequent icy obstruction is also responsible for Brazo Rico's insipid color, which is the result of sediment dislodged by its movements. The continued rising and falling of the river's surface has also carved out a border around its edges where no trees can grow.

Eagle-eyed viewers may have also spotted the narrow road winding across the Magallanes Peninsula and along the Brazo Rico's northern edge (just above the tree line): One can only imagine the extraordinary views you'd get to experience driving along there.

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This striking satellite photo captured a rare spectacle earlier this year, when "one of the driest places on Earth" experienced a rare snowstorm. This freak event temporarily turned the barren, rocky landscape white — and briefly shut down one of the world's most powerful radio telescopes.

The Atacama Desert is a roughly 40,500-square-mile (105,000 square kilometer) non-polar desert, located within a 1,000-mile-long (1,600 km) strip of land nestled between the Pacific Ocean and the Andes mountains in northern Chile. It is the world's oldest non-polar desert, having remained semi-arid for at least 150 million years. And it is home to the sunniest spot on Earth, the Altiplano Plateau, which experiences sunlight levels equivalent to those on Venus.

The desert is also widely considered to be one of the driest places on Earth, alongside other hyperarid spots, such as Antarctica and the Sahara. Some areas currently experience as little as 0.002 inches (0.5 millimeters) of rain annually, according to Guinness World Records. Previous research has hinted that parts of the Atacama went nearly 400 years without any recorded rain, between 1570 and 1971.

On June 25, a rare snowstorm hit Atacama after a "cold-core cyclone" unexpectedly drifted down from the north, covering over half the desert with white powder, according to NASA's Earth Observatory.

The satellite photo above shows a section of the desert in the Chajnantor Plateau, which rises to around 16,000 feet (5,000 meters) above sea level. This area is home to the Atacama Large Millimeter/submillimeter Array (ALMA) observatory — an array of more than 50 radio dishes that scour the "Dark Universe." (ALMA itself is not visible in the aerial photo.)

This area is well-suited to astronomical research because it is remote, dry and well-elevated, which reduces interference and maximizes the amount of data telescopes like ALMA can collect. But when the snow settled over the observatory, it temporarily forced ALMA into "survival mode," meaning that the dishes were repositioned to stop them from accumulating snow, halting observations.

The icy dust may have also affected the Southern Astrophysical Research (SOAR) Telescope, located around 530 miles (850 km) southwest of ALMA, but to a lesser extent, according to Live Science's sister site Space.com. The newly constructed Vera C. Rubin Observatory is also located in Atacama, near the SOAR telescope, but was not affected by the storm.

The snow did not last long, and most of it had disappeared by July 16. In some places, the sunlight was so intense that the snow likely sublimated, or turned directly from solid to gas, before it melted, according to the Earth Observatory.

This is not the first time that snow has fallen in the Atacama. Similar events also occurred in 2011, 2013 and 2021.

The region has also experienced several intense bouts of rain in recent years. When this happens, it can trigger deadly mudflows. In March 2015, at least 31 people were killed after heavy rainfall triggered Atacama's largest ever flood, according to a 2016 study.

Rain can also cause desert flowers, which normally appear in spring, to unexpectedly bloom during winter months, creating fields of vibrant petals to sprout up around the desert. This most recently happened in 2024, after a surprise rain shower caught the plants off guard.

Precipitation is rare in the Atacama for two reasons. Firstly, it sits within the "rain shadow" of the Andes, which block clouds moving in from the east. And second, cold ocean currents off the region's western Pacific coastline prevent water from evaporating into the air over the desert. This makes Atacama inhospitable to most lifeforms, aside from hardy desert flowers and extreme microbes that live well below its dry surface.

However, the recent instances of extreme precipitation in the region could be a sign that human-caused climate change is making it more likely for snow and rain to fall there. If this continues, the Atacama may one day no longer be one of the driest places on Earth.

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This eye-catching astronaut photo shows Yellowstone's eponymous lake covered in a thick blanket of snow, making it look like a colorless, featureless void in the surrounding landscape. But below this freezing, blank expanse lies some of the most active and hottest hydrothermal vents anywhere on Earth.

Yellowstone Lake is the largest body of water in Yellowstone National Park and the largest high-elevation lake in North America, sitting at 7,733 feet (2,357 meters) above sea level, according to the National Park Service (NPS). It is around 20 miles (32 kilometers) across at its widest point and has a maximum depth of 410 feet (125 m).

The lake freezes over every winter, around late December or early January, with an ice sheet that ranges from a few inches to around 2 feet (0.6 m) thick. But the blanket of snow on top of this ice can reach up to 3.5 feet (1.1 m) deep by March, according to NASA's Earth Observatory. The lake is usually snow- and ice-free by late May or early June.

The thick covering of snow means Yellowstone Lake is remarkably resilient to human-caused climate change, maintaining its surface ice thickness despite rising atmospheric temperatures. This makes it a major outlier among high-altitude lakes across the globe.

This astronaut photo shows one of these deep snowdrifts, mostly undisturbed aside from a few islands, the largest of which is Stevenson Island.

While the surface of Yellowstone Lake may seem cold and lifeless during the winter months, the water below remains surprisingly mild thanks to a series of hydrothermal vents across its floor. This enables aquatic animals, including the lake's cutthroat trout (Oncorhynchus clarkii) population — the largest of its kind anywhere in North America — to survive the long months under the ice, according to NPS.

One of the vents, right next to Stevenson Island, releases water that’s a remarkable 345 degrees Fahrenheit (174 degrees Celsius), making it hotter than Old Faithful and every other geyser or hot spring in Yellowstone National Park.

"This is much hotter than any surface hot spring at Yellowstone because the weight from the overlying lake water acts like a pressure cooker lid and allows temperatures higher than boiling to be reached," representatives from the U.S. Geological Survey wrote in an article about the lake's vents. "These are the hottest hydrothermal vents measured in a lake anywhere in the world."

The vents are powered by a giant blob of magma, around 2.6 miles (3.8 km) beneath Yellowstone National Park, which contains a surprising amount of molten rock. This magma blob acts like the cap on a gigantic volcanic bottle and will one day explode, unleashing a "supervolcanic" eruption that could be felt across the continent.

Yellowstone Lake was formed shortly after a similar eruption 640,000 years ago, which carved out the 1,500-square-mile (3,900 square kilometers) caldera that the lake currently sits within. Around 130,000 years ago, a smaller eruption then carved out the doorknob-shaped handle of the lake, dubbed West Thumb (visible near the top of the astronaut photo).

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This incredible astronaut photo captured a unique glimpse of Alabama's eponymous river cosplaying as a golden Chinese dragon. The metallic hue of the serpentine waterway is the result of a rare optical phenomenon that is only visible from space.

The Alabama River is a 318-mile-long (512 kilometers) waterway that stretches from the state's capital, Montgomery, past cities like Birmingham and Selma, and into Mobile Bay, where it drains into the Gulf of Mexico.

The section of the river in the photo features a large U-shaped bend, known as Gee's Bend, that surrounds the small town of Boykin, which is renowned for its "vibrant folk art" that is displayed across the country, according to NASA's Earth Observatory.

The river's unusual glow is the result of a rare phenomenon, known as a sunglint, which occurs when sunlight perfectly reflects off a still body of water toward an observer in space, like a massive liquid mirror. This is similar to how the surface of an ocean or lake sparkles when light bounces off it during a sunset — except the only people who can see it are astronauts.

The golden color of the sunglint helps provide greater contrast between water and land, highlighting a series of flooded zones. When combined with the river's larger bends, this makes the waterway look surprisingly like a dragon from Chinese mythology, netizens pointed out at the time.

The head of the dragon (located on the left of the image) is represented by the flooded zones of the artificial William "Bill" Dannelly Reservoir, which was created in the 1960s by partially damming the river. This 27-square-mile (70 square kilometers) reservoir generates hydroelectric power via a dam and has also become a popular fishing spot for people looking to catch crappie, bass and catfish.

The river's water levels rose higher than initially expected following the dam's construction, causing the waterway to permanently spill over into surrounding floodplains, such as at Chilatchee Creek (towards the bend in the dragon's tail) and around Gee's Bend, according to Earth Observatory.

Most bodies of water usually take on a silvery, mirror-like appearance when illuminated by sunglints, making the Alabama River's golden glow particularly noteworthy.

The unusual golden color is likely the result of atmospheric scattering of the reflected light by aerosols, dust and haze. This scatters blue wavelengths of light, giving the remaining light a more yellow hue.

Astronauts are always on the lookout for sunglints, especially over the ocean, because they can reveal hidden natural phenomena, such as gyres and internal waves, as well as human activities, such as ship wakes and oil slicks, according to the National Environmental Satellite, Data, and Information Service.

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This intriguing astronaut photo shows a trio of ancient "black mesas", which sit side-by-side in the Sahara desert. The dark structures have enabled a series of rare sand dunes to form around them while also creating a surprising "dune-free zone."

The three mesas, or flat-topped hills, are located around 8 miles (13 kilometers) northwest of the town of Guérou in southern Mauritania, which is home to around 22,000 people. The mesas are made from sandstone and rise steeply above the surrounding plains, reaching between 1,000 and 1,300 feet (300 and 400 meters) above the ground. The largest of the trio is approximately 6 miles (9.5 km) across at its widest point, while a fourth mesa is located just north of the trio, but is positioned just out of frame.

The dark color of these circular hills is the result of "rock varnish" — a black, clay-based coating, rich in manganese and iron oxides, that forms on exposed and arid rocks over thousands of years, according to NASA's Earth Observatory. This coating was likely partly fixed in place by microorganisms and is made up of multiple micrometer-thick laminations, according to Science Direct.

To the west of the mesas (on the left of the photo) is a barren rocky plain with a surprising lack of sand dunes. But to the east of the flattened hills, you can see several sizable dunes that are seemingly flowing away from the black rocks like a rippling tail.

There are two main types of sand dunes visible in the image. The first type are rare "climbing dunes," which are the larger, ridge-like piles of sand that have piled up along the mesas' eastern walls. The second type are "barchan dunes," which are more common and make up the mesas' stripy tail. In both cases, the dunes have a distinctive reddish-yellow hue.

The sand dunes only form on the eastern side of the mesas because the wind predominantly blows from that direction, carrying sand that then gets caught on the sloped elevations surrounding the black rocks.

Sand does not accumulate to the west of the mesas because of a phenomenon known as "wind scour," which results from superfast vortices within the wind that gets squeezed in between the mesas, which blow sand away from the flattened hills, according to the Earth Observatory.

Another astronaut photo, taken in 2014, shows this odd effect over a larger area (see below). In this shot, you can see the barchan dunes extend much further away from the mesas in the photo, as well as another larger mesa further east.

During the Paleozoic era, which lasted from 541 million to 251.9 million years ago, all these mesas were likely part of a single massive rock formation that has since been broken up by millennia of water and wind erosion, according to the Earth Observatory.

This formation may have been similar to the Richat Structure — a massive set of concentric rings of rock, also known as the "Eye of the Sahara," which is located in Mauritania around 285 miles (460 km) north of Guérou.

Mesas can be found across the globe but there is a particularly high concentration of them in the Sahara, as well as throughout parts of the U.S., such as Colorado, New Mexico, Utah, and Arizona, according to the National Park Service.

Elsewhere in the solar system, mesas are a prominent geological feature on Mars, having been carved out of the Red Planet by billions of years of wind erosion, according to Live Science's sister site Space.com.

For more incredible satellite photos and astronaut images, check out our Earth from space archives.

This striking satellite image shows two near-perfectly parallel tornado tracks in Mississippi that were carved into the ground after a deadly storm system triggered more than 100 twisters across the U.S. in early 2025.

Between March 14 and 16, a series of extreme thunderstorms broke out in the High Plains and Midwest thanks to an "expansive upper-level trough" of warm, moist air. This storm system triggered 113 tornadoes across 14 U.S. states, according to The Weather Channel. At least 42 people are believed to have been killed, according to NBC News.

One of the worst-hit states was Mississippi, which experienced 18 tornadoes. Half of these reached at least Level 2 ("considerable damage") on the Enhanced Fujita scale (EF Scale), which measures the damage caused by a tornado. Around 1,000 houses were damaged in the state, according to the Mississippi Emergency Management Agency. Dozens of businesses and farms were also hit.

In this satellite image, you can see two different tracks that were carved out by two separate tornadoes just outside of Tylertown, Mississippi. The longer and wider track stretches up to 55 miles (89 kilometers), while the smaller track is only around 9 miles (15 km) long. It is unclear which one appeared first, or how much time passed between the respective twisters.

Related: See all the best images of Earth from space

The larger of the two tornadoes is believed to have reached Level 4 ("devastating damage") on the EF Scale, making it the single most powerful twister of the entire storm system, according to NASA's Earth Observatory. Its wind speed likely reached 170 mph (274 km/h), which is equivalent to a Category 5 hurricane.

Around 50 miles (80 km) northeast of Tylertown, aerial photographs revealed another pair of tornadoes had passed at right angles to one another, creating a large X-shape in a forested area of Covington County, according to the National Weather Service station at Jackson, Mississippi.

2025 has been one of the worst years for U.S. tornadoes in recent memory, partly due to the recent La Niña phenomenon, which altered the trajectory of the Pacific jet stream above North America, creating drier and warmer conditions in southern states, according to the National Oceananic and Atmospheric Administration (NOAA).

March was particularly extreme, with a record 299 twisters recorded during that month, according to the National Centers for Environmental Information. (For context, the entire U.S. normally only experiences around 80 twisters during March, on average.)

But even without La Niña, the frequency of tornadoes has been increasing over time due to rising sea surface temperatures off the Gulf coast — a direct result of human-caused climate change.

Like other types of extreme weather, such as wildfires, heatwaves and floods, climate change is also making tornadoes more powerful, costly and deadly. In 2023, for example, at least 26 people were killed by a single, nearly mile-wide "wedge tornado" that ripped through parts of Mississippi.

Additionally, tornadoes are now starting to impact places where they have not historically been seen before. Some researchers have previously suggested that "Tornado Alley" — the central region of the U.S. where tornadoes are traditionally most likely to occur, in states such as Texas, Oklahoma, Kansas, Iowa and Nebraska — could now be considered to be everything east of the Rockies.

Researchers at NASA's Langley Research Center are currently working on a way to better predict when tornadoes will form by analyzing cloud patterns in satellite photos. They hope that this could eventually warn people about an impending twister up to 10 minutes before it happens, potentially saving many lives, according to the Earth Observatory.

This striking satellite photo shows an exceptionally dense and toxic algal bloom swirling in the waters of Nevada's Pyramid Lake. Some experts believe that the algae has existed in the lake for at least 9,000 years.

Pyramid Lake is a roughly 175-square-mile (453 square kilometers) lake, located northeast of Reno. It is around 27 miles (43 kilometers) across at its widest point and is named after a large pyramid-like rock formation located on a small island in the lake's southern half.

The lake is fed by a single river, but it is endorheic, meaning it has no outflow. As a result, it has a much higher salinity than most lakes, because excess water evaporates away, leaving its dissolved salts behind. The lake is also slightly alkaline and has a pH of around 9, which is roughly equivalent to baking soda.

Pyramid Lake experiences annual algal blooms between September and October, due to warmer temperatures and increased nutrient availability. The predominant algal species is Nodularia spumigena, which is a blue-green, nitrogen-fixing cyanobacteria that thrives in high-salinity waters, according to NASA's Earth Observatory.

But 2024's bloom, captured in this satellite image, was one of the most extreme in recent memory. It peaked on Oct. 15, around a week after this photo was taken. It is currently unclear why this bloom was so intense.

Related: See all the best images of Earth from space

N. spumigena has the potential to produce toxins, such as nodularin, which can affect the liver and cause other adverse health effects in humans and other animals. During the 2024 bloom, local authorities warned people to not let their pets anywhere near the water.

Pyramid Lake was once part of a much larger, prehistoric body of water, known as Lake Lahontan, which covered an area of around 8,000 square miles (21,000 square km) — around 45 times larger than Pyramid Lake.

This ancient lake was hit by climate change at the end of the last ice age, or Pleistocene epoch, which ended around 12,000 years ago. Around 3,000 years later, Lahontan had essentially disappeared, leaving Pyramid Lake as its largest remaining remnant.

Today, Pyramid Lake is known for a series of striking pillar-like calcium carbonate features, known as tufas, which grew from Lake Lahontan's receding waters between 26,000 and 13,000 years ago, according to the U.S. Geological Survey. (This includes the pyramid-like structure the lake is named after.)

A 1990 study analyzed trends across 15 consecutive N. spumigena blooms in Pyramid Lake between 1972 and 1986. The researchers theorized that the cyanobacteria once bloomed in Lake Lahontan and may have persisted in its remaining waters ever since.

Pyramid Lake is also home to the cui-ui (Chasmistes cujus) — an endangered species of suckerfish that isn't found anywhere else on Earth. These fish feed mainly on algae, such as N. spumigena, and also likely used to dwell within Lake Lahontan.

This striking satellite photo shows a barren Mars-like volcano lurking in the heart of the Costa Rican rainforest. The alien landscape contains a super-acidic lake that is a "paradise" for extreme microbes and provides researchers with an excellent analog for studying potential lifeforms on the Red Planet.

The unique volcano, named Poás, is the focal point of the Poás Volcano National Park in Costa Rica's Alajuela province. It is a stratovolcano that formed between 1.5 million and 700,000 years ago, with a summit that reaches 8,848 feet (2,697 meters) above sea level.

Satellite images make it look like Poás is situated in the middle of nowhere. However, around 10 miles (16 kilometers) southeast of the volcano (just out of shot in this photo), lie the suburbs of Costa Rica's capital San José, which is home to around 1.5 million people. As a result, the volcano is a popular tourist destination, despite being one of the most active volcanoes in Central America.

Poás has had dozens of major eruptions in the last 200 years, but also experiences many more smaller outbursts, where it puffs out a mix of steam, smoke and toxic gases, as well as the occasional ash cloud. Since 2005, the volcano has had 13 of these minor eruptive phases, according to the Smithsonian Institution's Global Volcanism Program.

Its most recent eruption began on Jan. 5 and persisted for the majority of 2025, although it has likely now come to an end. This phase's activity peaked in early May, when sulfur dioxide levels briefly impacted air quality in San José and ashfall damaged some nearby crops, according to NASA's Earth Observatory.

Related: See all the best images of Earth from space

The main crater of Poás contains a highly acidic volcanic lake, named Laguna Caliente, which has an average pH value of just over 0, which is roughly equivalent to battery acid, according to the Earth Observatory. This crater, which is around 0.8 miles (1.3 km) wide, is also home to sporadic geysers.

While these extreme conditions mean no animals or plants live within the crater, the lake's acidic waters are home to a thriving microbial community dominated by extremophile bacteria in the genus Acidiphilium, which feast on metal compounds dissolved in the water.

"We have a very human-centric bias for what a nice, happy, temperate environment is to grow in," Rachel Harris, a microbial ecologist and geochemist at Harvard University who is currently involved in devising NASA's Decadal Astrobiology Research and Exploration Strategy, told the Earth Observatory. "The Poás system may be hostile to most forms of life we are familiar with. But for a microbe adapted to acid, heat and toxic metals, it's paradise," Earth Observatory representatives added.

Researchers are interested in Poás' extreme ecosystem because it is very similar to volcanic environments that likely existed on Mars more than 3 billion years ago, when the Red Planet was more similar to our own.

A 2022 study, for example, revealed that the low biodiversity and high resilience within Laguna Caliente's microbial community is very close to what researchers expect could have developed within potential Martian ecosystems.

Poás is particularly similar to a region of Mars, known as Home Plate, which was surveyed by NASA's Spirit rover in 2009. This 300-foot-wide (90 m) plateau likely had an acidic hydrothermal system that may have been almost identical to Laguna Caliente, according to the Earth Observatory.

Other types of extremophiles may also have once thrived on Mars, including lifeforms similar to lichens or photosynthetic algae. However, despite some promising recent findings from NASA's Perseverance rover, there is no hard evidence that the Red Planet has ever supported alien life.

This striking satellite photo shows a gigantic geoglyph, dubbed the "Marree Man," which suddenly appeared in the Australian outback less than 30 years ago. The origins of the Aboriginal-inspired artwork remain a mystery.

The Marree Man, also known as "Stuart's Giant," is a geoglyph — a large-scale design or symbol made by altering Earth's surface in some way. In this case, it was carved directly into the Finniss Springs plateau of South Australia, around 37 miles (60 kilometers) west of the township of Marree, according to NASA's Earth Observatory.

The figure's design is likely based on an Aboriginal Australian, who is depicted naked and brandishing either a "woomera" throwing stick or a boomerang. It is around 2.2 miles (3.5 km) across at its widest point, from the bottom of its feet to the tip of the weapon, while its perimeter measures around 17 miles (28 km) in total.

Compared with most other geoglyphs — such as Peru's Nazca Lines, which may date back as far as 200 B.C. — the Marree Man is extremely young, having suddenly appeared in the summer of 1998. But experts are unsure who created the towering figure or how they sketched it out so quickly.

Related: See all the best images of Earth from space

By 2016, the lines of the Marree Man, which were originally around 10 inches (25 centimeters) deep, had almost completely disappeared due to wind erosion.

As a result, local business owners decided to recarve the lines using a commercial digger and GPS guidance system, resulting in much deeper lines, according to ABC News.

The retraced geoglyph, which is shown in the satellite image, should last longer than its predecessor (see below) because special grooves designed to trap water were added to its outline. In theory, this should allow vegetation to grow around its edges, giving it a longer-lasting green border, according to the Earth Observatory.

Who made the Marree Man?

The Marree Man was first discovered by a charter pilot on June 26, 1998, shortly before an anonymous fax was sent to nearby hotels, alerting the staff of the geoglyph's creation and initially naming it Stuart's Giant. (The name Marree Man was later popularized by the press.)

Satellite imagery from Landsat 8 subsequently revealed that it was created at some point during a 16-day period between May 27, when no geoglyph was visible to the satellite, and June 12, when it was first photographed from space.

It was likely created by some type of earth-moving machinery, and some experts argue that it could only be achieved using an early form of GPS mapping.

When the lines were redrawn in 2016, it took workers around 60 hours to complete the task using updated technology. The team also found 250 bamboo stakes along the perimeter, which were likely used as markers for the original, according to a 2016 article by Expedition Australia.

The most commonly proposed creator of the Marree Man was an Adelaide-based artist named Bardius Goldberg. Several of Goldberg's friends have claimed that he told them he was responsible, but he never publicly admitted this, and died in 2002.

There is also evidence that it may have been created by American personnel at a nearby Royal Australian Air Force base, as a small plaque with the U.S. flag was uncovered near the giant's head. Experts have subsequently pointed out that the anonymous fax also contained several "Americanisms," according to ABC News.

In 2018, Australian entrepreneur and explorer Dick Smith offered a 5,000-Australian-dollar (U.S. $3,700) reward for anyone with information about the geoglyph's origins, according to CNN.

This eerie astronaut photo shows a ghostly structure with a skull-like appearance glowering up into space from the floor of a giant volcanic pit in the Sahara.

The cranium lookalike is located on the floor of Trou au Natron, also known as Doon Orei — a 3,300-foot-wide (1,000 meters) volcanic caldera, or crater, in northern Chad. (Trou au Natron translates to "natron hole" in French, while Doon Orei means "big hole" in Teda.)

The volcanic pit was carved out by a massive eruption hundreds of thousands of years ago and sits at the heart of the Tibesti Massif, a 300-mile-long (480 kilometers) mountain range that stretches across the center of the Sahara desert through Chad and Libya, according to NASA's Earth Observatory.

When viewed from space, the caldera's floor has an unmistakable skull-like appearance. But when viewed from ground level (see below), it looks almost unrecognizable.

Related: See all the best images of Earth from space

The white color of the skull's mouth, nose and cheeks is the result of natron, a naturally occurring mixture of sodium carbonate decahydrate, sodium bicarbonate, sodium chloride and sodium sulfate. This salty mix is extremely flaky and looks like cracked paint when viewed up close.

The eyes and nose hole areas are actually cinder cones — steep conical hills built around volcanic vents that tower above the rest of the caldera floor. The darker area to the left of the face is the shadow cast by the tall rim of the crater, which helps give the skull its distinctive shape.

Trou au Natron is barren and lifeless today, but experts believe it was once a thriving glacial lake. In the 1960s, researchers discovered fossils of sea snails and plankton beneath the pit's natron-covered floor, which date back to 14,000 years ago. In 2015, a follow-up expedition found algal fossils that date back as far as 120,000 years ago.

The caldera has been volcanically dormant since shortly after it formed. However, it is situated close to Tarso Toussidé, a broad volcanic feature covered with a sea of frozen lava (located just beyond the top of the satellite image). Tarso Toussidé is home to a stratovolcano that is still believed to be volcanically active despite not erupting for more than 12,000 years, according to the Smithsonian Institution's Global Volcanism Program.

Trou au Natron is not the only volcanic structure that looks like a skull when viewed from space: The Chiltepe Peninsula in Nicaragua's Lake Managua has a pair of volcanic lakes, each sitting within its own caldera, which give the landmass a very similar appearance to the caldera in Chad.

This intriguing astronaut photo shows a pair of islands in the murky green waters of a major African lake. Both landmasses are home to monasteries that hold important religious relics, including the remains of several ancient emperors.

The two islands, named Dek and Daga, are located within Ethiopia's largest body of water, Lake Tana, which has an average surface area of around 1,200 square miles (3,100 square kilometers) — around the same size as Rhode Island. The lake, which is listed as a UNESCO biosphere reserve, is located in the Ethiopian Highlands, around 5,800 feet (1,770 meters) above sea level, and has a maximum depth of around 50 feet (15 m).

Lake Tana was formed around 5 million years ago when volcanic activity dammed a group of ancient rivers. It is now the major source of the Blue Nile — a 900-mile-long (1,450 kilometers) tributary of the Nile River that flows through Ethiopia and Sudan.

Dek, the larger of the two islands, measures around 4.5 miles (7.5 km) across at its widest point and has a population of around 5,000 people, while Daga has a maximum width of around 1 mile (1.6 km) and is not permanently inhabited.

When viewed from above, the islands stand out against the lake's insipid milky-green coloring, which is the result of algal blooms that thrive off nutrients from agricultural runoff and wastewater, according to NASA's Earth Observatory.

Related: See all the best images of Earth from space

Dek is an agricultural hotspot thanks to its nutrient-rich volcanic soils and high rainfall, which is due to its location in the Intertropical Convergence Zone — a low-pressure belt near the equator that experiences frequent thunderstorms. Most of the island's surface has been transformed into agricultural fields, which appear light brown and red when viewed from above. Their main crops are corn, millet, coffee and mangos.

In the photo, a bright orange lake is situated towards Dek’s southeastern corner. It is unclear exactly what gives this lake its vibrant hues, but it is also likely tied to agricultural runoff, according to the Earth Observatory.

However, the two islands' most interesting sites are probably their monasteries, which cannot be easily seen from space.

Holy relics

Experts believe that there is at least one church or monastery on more than half of the 30 or more islands within Lake Tana (the total number of islands within the lake is disputed because some only appear during the rainy season, when the lake expands). These religious sites were created, in part, to protect Ethiopia's most valuable relics and treasures during times of war, according to the Earth Observatory.

Dek is home to at least five churches, as well as the 18th-century Narga Selassie monastery, which is filled with stunning paintings of Ethiopian history. However, Daga is arguably home to a more important monastery, named Daga Estifanos or "St. Stephen of Daga," which dates to the 13th century.

The mummified remains of at least five Ethiopian emperors — who ruled the country at various points from between 1270 and 1730 — are kept at Daga Estifanos, and are each displayed for tourists in special glass-sided coffins, alongside crowns, scrolls and other artifacts from their reigns, according to the Lake Tana Biosphere Reserve website.

But, due to local customs, only men are allowed to visit Daga and its monastery. In fact, the local "no females" rule is even applied to farm animals.

Other major religious sites in Lake Tana include Tana Cherkos, an island populated exclusively by monks from the Ethiopian Church. The Ark of the Covenant was supposedly kept there for around 800 years, sometime after it was stolen from Jerusalem and before being moved to the Ethiopian mainland, according to the Lake Tana website.

This striking satellite photo shows a particularly convoluted section of a record-breaking "braided river" in China, which drastically changes shape every year and could become more unstable over the coming decades due to climate change.

The Yarlung Zangbo River is a roughly 1,250-mile-long (2,000 kilometers) waterway that stretches from its origin at a glacier in the eastern Tibetan Plateau all the way into India. It is the longest river in Tibet, as well as the fifth longest in China, and holds the record for being the highest major river on Earth, flowing at an average elevation of 4,000 meters (13,000 feet) above sea level, according to NASA's Earth Observatory.

The photographed section of the river is located in Zhanang County, just before it passes through the world's deepest land-based canyon and its namesake, the Yarlung Tsangpo Grand Canyon, which is more than 6,000 meters (20,000 feet) deep — or three times deeper than Arizona's Grand Canyon.

Yarlung Zangbo is a classic example of a braided river — a waterway with "multi-threaded channels that branch and merge to create the characteristic braided pattern," with mid-channel sandbars that are "formed, consumed, and re-formed continuously," according to the National Park Service.

This section is where the most braiding occurs anywhere along the river, with up to 20 channels across at certain points in the image.

Related: See all the best images of Earth from space

Yarlang Zangbo's extreme braiding is caused by heavy sediment deposits from the steep slopes of the adjacent Himalayas, which are washed into the river and help carve new channels into the ground, Zoltán Sylvester, a geologist at the University of Texas at Austin, told the Earth Observatory. The river changes shape so often that no vegetation can fully grow on the sandbars that sporadically appear between the river's braids, he added.

You can see how quickly the river changes shape for yourself in a 37-year timelapse animation, which shows annual satellite images of this spot taken between 1988 to 2025 by Landsat 5, Landsat 8 and Landsat 9 (see below).

Eagle-eyed viewers may also be able to spot a narrow bridge, which was constructed over the shapeshifting waterway in 2014. (It's visible as a thin line near the far right-hand side of the animation).

The river starts at the Angsi Glacier, emerging from a stream of meltwater that flows from the ice mass. However, this was only officially confirmed in 2011, according to Chinese state media. Before this, there was confusion among scientists about whether the river actually originated from a meltwater stream coming from the nearby Chemayungdung Glacier.

Like many other Himalayan ice masses, the Angsi Glacier has lost a significant amount of water in recent decades due to human-caused climate change. The resulting meltwater has caused more sediment to be deposited into the river, which can increase erosion and make it more likely for its banks to collapse. According to a 2024 study that analyzed satellite photos of the 13 major rivers in the Tibetan Plateau, this poses a risk to local ecosystems, infrastructure and landscape stability.

When the river eventually reaches India, it becomes part of the Brahmaputra River and continues for another 1,800 miles (2,900 km) until it reaches the Ganges River Delta, where it drains into the Indian Ocean, according to the Earth Observatory.

This amazing astronaut photo shows the bizarre whale-like shape of a Belizean tropical island. The coral-reef-covered structure is home to the Great Blue Hole, one of the deepest marine sinkholes on the planet, which appears to double as the whale's "blowhole" when viewed from space.

The cetacean-shaped landmass, known as Lighthouse Reef, is located around 50 miles (80 kilometers) off Belize's eastern coast in the Caribbean Sea, and is around 26 miles (42 km) long from its "head" to its "tail." It has no permanent human population, but it's visited by more than 10,000 tourists, including many scuba divers, every year.

The island is an atoll, meaning it is mostly underwater and covered by shallow coral reefs, with only a few sandy patches, known as cays, poking above the ocean's surface. The atoll's turquoise waters are only between 6 and 20 feet (2 and 6 meters) deep, but near the island's center lies a dark circle that goes far, far deeper.

The Great Blue Hole is an underwater sinkhole with a near-circular opening that spans 1,043 feet (318 m). It has a maximum depth of 407 feet (124 m) — making it one of the deepest sinkholes on Earth — and it has only recently been properly explored.

Related: See all the best images of Earth from space

Lighthouse Reef is part of the wider Belize Barrier Reef, which is listed as a UNESCO World Heritage Site, and is home to a range of marine life, including a variety of fish, such as wrasses, snappers and gobies, as well as larger animals, such as crocodiles and sea turtles.

One of the island's most notable above-water spots, Half Moon Caye (located on the tip of the hump on the whale's back), is also home to a variety of birds that nest within its coconut trees, as well as endangered species of gecko and anole.

Great Blue Hole

The Great Blue Hole is believed to have initially formed as an above-water cave system, as evidenced by the stalagmites and stalactites found in submerged caves that branch off from the main sinkhole. However, it was flooded around 10,000 years ago as the end of the last ice age caused sea levels to rise.

The hole was made famous in the 1970s when the renowned ocean explorer Jacques Cousteau visited the island and started charting its depths from his famous ship, the Calypso. Cousteau later described the sinkhole as one of his "top five scuba diving sites" in the world.

In 2018, the explorer's grandson Fabien Cousteau and British billionaire Richard Branson led a submarine expedition to explore the Great Blue Hole and created the first 3D map of the structure. One of the standout findings from this expedition was the discovery of a layer of hydrogen sulfide, around 107 feet (33 m) thick, toward the bottom of the hole. This layer is anoxic, meaning it contains no dissolved oxygen, which makes it deadly for most marine animals that venture into it.

The expedition team also discovered the bodies of two scuba divers who had previously gone missing while exploring the Great Blue Hole; their bodies had been perfectly preserved by the hydrogen sulfide layer, according to Newsweek. The expedition team decided to leave the bodies where they were, out of respect. At least one other diver is known to have gone missing in the sinkhole.

More recently, earlier this year, scientists used sediment cores collected from the sinkhole's floor to analyze historic tropical cyclones in the area and found that these storms have become more frequent over the past 6,000 years.

This striking satellite image shows the stark difference between a giant field of sandy "stars" and a barren rocky wilderness in the Sahara Desert. The contrasting biomes also overlap with the border where two African countries meet.

The sea of orange sand visible in this image is part of the Grand Erg Oriental — a giant field of dunes, or erg, that covers around 55,000 square miles (140,000 square kilometers) in the northern Sahara.

This part of the erg has hundreds of prominent "star dunes," which have at least three ridges coming from a central peak, giving them a star-like appearance when viewed from above. Star dunes can grow to be over 300 feet (90 meters) tall and only form in locations where wind directions change constantly, which allows their different slopes to form, according to the National Park Service.

The dunes overlap with a windswept rocky terrain, which is among "the driest parts of the Sahara Desert" and almost completely devoid of vegetation, according to NASA's Earth Observatory. This terrain is covered with overlapping geological features, giving it an otherworldly quality.

One of the most striking features is a large white patch in the heart of the rocky terrain, which is the remnant of an ancient lake. You may also be able to see a series of parallel grooves in the rock (in the top half of the rocky terrain), which were carved by eons of unidirectional winds that blew long before the multi-faced dunes were formed.

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The dunes in the image are all located within Algeria, while most of the rocky terrain is in Libya. The invisible boundary between the two countries is largely located down the very center of this image. However, at one point, just to the left of a Libyan town called Ghadames (visible as a dark spot near the top of the image), the border between the countries almost exactly overlaps with the line where the sand and rock meet.

While the contrasting ecosystems appear to have nothing to do with each other, they are more linked than you might imagine. Geologists believe that a majority of the erg's sand was deposited by ancient rainwater that took loose sediments from the rocky terrain and dumped them within a natural depression, or sink, in the landscape.

This process likely took hundreds of thousands, if not millions, of years — and if you look closely, you can see that some of the erg's sand has spilled back out into the ancient "winding water courses" that helped to deposit the sand within the erg, according to the Earth Observatory.

The erg is also partly formed above the bed of an ancient river. When rain infrequently falls on the erg's sands, the moisture is funneled away into underground aquifers, which can support pockets of vegetation on the surface. If this did not happen, this valuable moisture would quickly evaporate back into the atmosphere.

This striking satellite image highlights the aftermath of a major hailstorm in Alberta, Canada, which carved a giant "scar" in the landscape, around half as long as the Grand Canyon. The extreme event, which pelted the ground with golf ball-size ice chunks, killed at least two animals.

On Aug. 20, on what had otherwise been a calm day, a surprise storm began in a localized region of southern Alberta after the arrival of a "supercell" — a rare type of thunderstorm that contains a deep and persistent rotating updraft, according to NASA's Earth Observatory.

While the storm produced few lightning strikes, it triggered a serious hailstorm and high winds that caused widespread damage to houses, vehicles and infrastructure. Some of the hailstones reached a maximum diameter of 2 inches (5 centimeters), and the associated winds reached speeds of over 75 mph (120 km/h) — equivalent to a Category 1 hurricane, according to The Weather Network.

In addition to damaging property, the giant balls of falling ice hammered into the ground and tore up vegetation. The result was a roughly 125-mile-long (200 kilometer) and 9-mile-wide (15 km) scar etched across the landscape, which was clearly visible from space.

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The worst-affected area was around Brooks, a small city located around 100 miles (160 km) southeast of Calgary (visible in the top left of the satellite image). The combination of supersized hail and high winds damaged local houses and vehicles, as well as wrecking nearby power pylons, some of which were bent at a near 90-degree angle, Canadian news outlet CBC reported.

"The whole front of the house is destroyed," Brooks resident Colleen Foisy told CBC. "The front fence actually got ripped off of the cemented posts. My flowers in my garden got thrown around, branches from the trees. There's hail damage all over my truck that's only a year old. The cover to my boat got shredded."

The high winds also blew over a large fence at the White Barn Fun Farm, located west of Brooks, killing a Bactrian camel (Camelus bactrianus) and pony that were "best friends," the farm's owner told CBC. A horse and several birds were also injured.

"Hailstorm alley"

While this event was extreme, it is not unusual for such storms to appear in this part of Alberta, which is often dubbed "hailstorm alley."

"The region's climate and geography are conducive to storm development, and the area typically sees dozens of hail events each year," Earth Observatory representatives wrote.

Over the last five years, hailstorm damage in Alberta has totaled more than 6 billion Canadian dollars ($4.3 billion), excluding damages from August's storm, which are yet to be calculated, according to a recent report from Insurance Business magazine.

Some of the people affected by the most recent storm were still recovering from a similar event in July.

Researchers at NASA's Langley Research Center are now working on a way of being able to better predict these damaging storms in advance, to help mitigate their impacts.

"With state-of-the-art identification techniques, we can quantify severe storm distribution and frequency with an exceptional level of consistency that's only granted by satellite measurements," Benjamin Scarino, a research scientist at the center, told Earth Observatory. "Long-term satellite data records allow us to provide the reinsurance industry, project partners, and the research community with valuable insights into severe storm activity and risk."

This intriguing astronaut photo shows two volcanic lakes appearing to peer into space from a skull-like peninsula in Nicaragua, like a pair of heterochromatic googly eyes. This unusual scene, which is influenced by a subtle optical illusion, is completely unrecognizable from ground level.

If these lakes are considered eyes, then their head is the Chiltepe Peninsula, a rounded landmass that extends into the waters of Lake Managua. Known locally as Lago Xolotlán, it covers an area of around 400 square miles (1,040 square kilometers) in the heart of the Central American nation.

The peninsula, located around 10 miles (16 km) northwest of the capital city of Managua, was formed by a series of pyroclastic shield eruptions. During these blasts, mostly low-density materials, such as pumice, are violently ejected from beneath the surface, according to NASA's Earth Observatory. These major eruptions ended around 17,000 years ago. However, more recent volcanic activity has occurred there within the past 2,000 years.

The smaller lake (on the left), which is around 1.1 miles (1.7 km) wide, is located within the Apoyeque caldera. The larger lake (on the right), known as Laguna Xiloa, is around 1.5 miles (2.4 km) across at its widest point. It was formed by an explosive outburst that occurred when magma from below Apoyeque interacted with submerged groundwater.

When viewed from space, the lakes appear side by side. However, the surface of the Apoyeque lake sits at an altitude of around 1,300 feet (400 m), while Laguna Xiloa is close to sea level — meaning you would not be able to see both unless you stood on the crater rim of Apoyeque.

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The two lakes are slightly different colors: Laguna Xiloa is a deep blue, while Apoyeque is greenish. If these bodies of water were really eyes, then they would be a rare example of heterochromia — a rare condition in which a person's eyes are different colors.

At first glance, the two lakes have a fairly similar size and shape. However, Apoyeque's lake is smaller and more rounded than Laguna Xiloa. The reason for this subtle illusion is that the rim of Apoyeque's crater is much more closely aligned to the outline of Laguna Xiloa, making them seem more similar at first glance.

Explosive potential

Both Apoyeque and Laguna Xiloa are technically active volcanoes, but they have not erupted for millennia and are unlikely to do so anytime soon, according to the Smithsonian Institution's Global Volcanism Program.

Laguna Xiloa last erupted approximately 6,000 years ago, whereas Apoyeque has had four major eruptions since then. The most recent and explosive of these is estimated to have occurred in around 50 B.C. and sculpted the shape of the crater that now holds its lake.

In 2012, a swarm of minor earthquakes was triggered by the movement of magma beneath Apoyeque, according to the Earth Observatory. However, this was not a sign of an imminent eruption.

If the larger volcano were to blow its top, it could impact some of the residents of Managua, as well as significantly endanger the residents of Bosques de Xiloa, a small town on the shores of Laguna Xiloa (visible in the satellite image).

This intriguing astronaut photo shows a patch of land in Idaho that looks strikingly like a giant chessboard when viewed from space. The strange pattern comes from an environmental initiative dating back roughly 200 years.

The aerial shot shows a tract of land alongside the Priest River in the mountains of northern Idaho, around 40 miles (65 kilometers) south of the Canadian border. The closest point of interest is Whitetail Butte, a lookout point for forest fires, which is positioned on a large bend in the river (roughly halfway along the waterway in the photo).

The "chessboard" is around 5 miles (8 km) across at its widest point and contains approximately 185 squares, although not all of them are visible in this photo. Each square covers around 1.4 million square feet (130,000 square meters) — about the same size as 24 football fields.

This pattern results from a grid-based forest management initiative set up in the 1800s. Alternating squares have been cleared for their timber, leaving enough trees to sustain the forest ecosystem while new trees grow, according to NASA's Earth Observatory.

New trees are then planted in the empty squares. When the trees have fully matured, the trees on alternating squares are harvested, and the cycle begins again. This photo was likely taken just a few years after the most recent harvest.

The pattern has been accentuated by snow, which has settled on top of saplings in the "empty" white squares. The checkering is also visible during the summer. However, there is much less distinction between some light and dark squares, which appear as various shades of green.

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This photo was taken just before sunset, so some mountainsides glow while others are covered in long shadows due to the low angle of the sun.

The Priest River, which is part of the Columbia River basin, was previously used to transport timber from this region to sawmills in other parts of Idaho and beyond. This was traditionally done by "log driving," which involved floating rafts of logs on the river's surface, often with people standing on top and using long poles to redirect the rafts and prevent them from jamming.

However, this practice was halted in the 1990s to allow for more recreational uses of the river.

The logs are now transported by road, and if you look closely, you can see the faint line of a purpose-built trucking road passing diagonally through multiple squares of the checkered forest.

This intriguing astronaut photo shows off an oddly shaped field of dunes in Kazakhstan that strongly resembles a giant slug meandering across the landscape. The mollusk mimic is covered with clusters of vegetation, suggesting its sands are slowly being frozen in place.

The dune field is located around 175 miles (280 kilometers) northeast of the Caspian Sea in the western reaches of the Kazakh Steppe — a vast region of open grassland covering north Kazakhstan and parts of Russia. It is sandwiched between the village of Oyyl to the west (left in the image) and a large floodplain to the east (right in the image).

It covers an area of around 75 square miles (190 square kilometers), around three times the size of Manhattan, and measures approximately 13 miles (21 km) across at its widest point, according to NASA's Earth Observatory.

Dune fields form in natural depressions, or sinks, within the surrounding landscape, normally in regions with high winds capable of depositing sand in these holes. In this case, the slug-shaped sink sits approximately 300 feet (90 meters) below the elevation of the surrounding landscape.

Most of the sand within this sink originates from the adjacent floodplain, as well as another floodplain located to the south (not shown in the image). Floodplains generate lots of sand when they dry out, as previously trapped coarse sediments get scattered across the land and blown away by the wind, according to National Geographic.

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The parallel lines visible across the dunes are ridges of sand built up as the prevailing wind pushes the sand northward. Over time, the positions of these ridges subtly shift in the same direction.

The dark patches littered across the dune field are plants that have taken root in the ridges. If the concentration of this vegetation gets high enough, it can fix a ridge into place and prevent it from moving, similar to some of the dunes frozen in place along various coastlines across the globe.

Most of the vegetation is concentrated along the southern and western edges of the dune field, likely due to water coming from the Uil River, which snakes around the outskirts of Oyyl, according to the Earth Observatory.

Scientists are currently uncertain if the rest of the dune field will follow suit and become overrun by plant life in the future.

This stunning astronaut photo shows a series of milky swirls that appeared in the waters of Turkey's Lake Van, the largest "soda lake" on Earth. While the swirls look like a common natural phenomenon, they're actually something much rarer.

Lake Van is the largest lake in Turkey with a surface area of around 1,200 square miles (3,100 square kilometers), which is slightly smaller than Rhode Island. Its surface is located at an altitude of 5,380 feet (1,640 meters) above sea level and has a pH of around 10, which is highly alkaline.

The photo above shows a section of Lake Van around the city of Erciş, which is located along the lake's north shore. The swirls in the image look very similar to shapes that appear during algal blooms, when rapidly multiplying plankton species get caught up in wind-driven currents. However, this was not the cause of these swirls.

Instead, the milky material in the lake is mostly made up of calcium carbonate, as well as smaller concentrations of detritus — waste organic material left over from living and dead animals, according to NASA's Earth Observatory.

This milky swirls are known as "turbidity plumes," clouds of suspended material that are triggered by natural or human-caused disturbances to the lake floor. These plumes are more likely to appear in this part of the lake because the water level is shallower than the rest of the lake, which reaches a maximum depth of around 1,450 feet (450 m).

Related: See all the best images of Earth from space

Lake Van also has one of Earth's highest concentrations of "microbialite," a collection of free-floating organo-sedimentary structures formed by the trapping, binding and precipitation of minerals by various microbes. Microbialite production peaks in the spring and fall, when microbial communities multiply. However, this is not thought to be the cause of these particular swirls, according to the Earth Observatory.

The lake's high pH levels are caused by high concentrations of carbonate salts, which have built up over time because the lake is "endorheic," meaning it does not have an outlet. Therefore, as water evaporates from the lake, the concentration of salts increases.

The salt concentration in the lake is so high that the water rarely freezes, even though its temperature frequently drops below 32 degrees Fahrenheit (0 degrees Celsius) during the winter months.

Lake Van's water levels have changed significantly over the last 600,000 years as changes in Earth's climate have altered the rates of water input and evaporation. A 2014 study estimated that its depth has fluctuated by around 2,000 feet (600 m) during this time.

While the large milky swirls in the photo are not caused by algal blooms, you can see small concentrations of phytoplankton that have accumulated along Erciş' coastline, as well as within a smaller lake located near the top of the image.