Scars on Mars
European Space Agency's (ESA) Mars Express recently returned new images of an elongated impact crater in the southern hemisphere of Mars. Located just south of the Huygens basin, it could have been carved out by a train of projectiles striking the planet at a shallow angle, researchers say. The unnamed depressed is about 48 miles (78 kilometers) in length and reaches a depth of 1.2 miles (2 km). Here, purple indicates the lowest lying regions and gray the highest (scale in meters).
Impact craters are generally round, because the projectiles that create them push into the ground before the shockwave of the impact can explode outwards. As for why this crater is elongated, the researchers found the answer in the surrounding blanket of material (called the ejecta blanket). This ejecta blanket is shaped like a butterfly's wings, with two distinct lobes, suggesting that two projectiles, possibly halves of a once-intact body, slammed into the surface here.
far side of the moon
Martian Valley Captured by Viking
On Orion's Sword
Massive stars light up the Orion nebula, seen here as the bright area near the center of the image. To the north of the Orion nebula is a dark cloud of cold dust and gas. Here, a new generation of ruby red protostars jewel Orion's sword. NASA's Spitzer Space Telescope, which captured this image, recently detected tiny green crystals raining down on one of these baby stars like glitter from a surrounding gas cloud.
Big Storm, Little Moon
In comparison, little Io looks relatively peaceful. But the moon is home to more than 100 active volcanoes, which spew out hot lava and giant plumes of dust and gas.
— Stephanie Pappas
Jupiter & Crescent Moon Light Up the Night
Spiral in Space
This photo was taken a year and a half after the supernova explosion, so the brilliance of the white dwarf's last breaths is no longer visible. But NGC 634 still sparkles from its perch in the Triangulum constellation, 250 million light years away from Earth.
— Stephanie Pappas
Solar Storm May Spark Dazzling Northern Lights Display
Skywatchers at high latitudes can expect spectacular aurora borealis displaysin the skies tonight (Aug. 5) thanks to a strong solar flare that hurled a cloud of plasma toward Earth on Aug. 2. The flare occurred when an intense magnetic event above sunspot 1261 hurled a stream of charged particles that's now headed toward Earth, according to SpaceWeather.com.
Also known as the Northern Lights, the aurora light show is the result of the interaction of these charged particles with Earth's magnetic field.
The image above, taken by instruments onboard NASA's Solar Dynamics Observatory, shows a powerful M9-class solar flare that erupted from the sun at 10:09 p.m. EDT on July 29 (0209 GMT July 30). M-Class flares are medium-strength events. The strongest type of solar eruption is class X, while class C represents the weakest, on the scale. The Aug. 2 flare registered as a middleclass M1 event. [Read more at SPACE.com]
Merging Galaxies Form Cosmic Exclamation Point
A Great Comet Sets
Sparkling Spirals: Our Galaxy Is Born
Astrophysicists have long tried to simulate the formation of our spiral galaxy, the Milky Way. Until now, such attempts have faltered on one of two points: Either the simulated spiral galaxies displayed too many stars at the center or the overall stellar mass was several times too big.
For their study, which is published in the Astrophysical Journal, the scientists created a computer model of a spiral galaxy similar to the Milky Way developing by itself without any intervention, offering a glimpse in time lapse into almost the entire genesis of a spiral galaxy. The above image shows our simulated galaxy (left), with gas in red and stars in blue, along with a false-color picture of the spiral galaxy M74.
The simulations, among other findings, showed that stars must be at the outer edge of the Milky Way.
Being able to use physical laws and processes to recreate the formation of a complex system like the Milky Way realistically is the ultimate proof that the underlying theories of astrophysics are correct.
An Amazing Race ... Around Saturn
Swirl of Stunning Stars
The distorted shape of the larger of the two galaxies shows signs of tidal interactions with the smaller of the two. It is thought that the smaller galaxy has actually passed through the larger one.
Feeding the Beast
No one has ever seen this process in real life; rather, this version of galaxy formation is a theoretical scenario based on numerical simulations.
Silver Sliver in the Sky
Jelly With Your Fried Egg?
For sure this would be one giant (and explosive) breakfast. Spanning 1,000 times the diameter of the sun, this monster star known as IRAS 17163-3907 shines some 500,000 more brightly than the sun, researchers have just found. New observations of the star and its surrounding shells using the infrared camera aboard Very Large Telescope (VLT) revealed it is actually a yellow hypergiant. [50 Fabulous Deep-Space Nebula Photos]
If the fried egg nebula, which includes the star and its surrounding cloud of gas and dust, were placed in the center of the solar system, Earth would lie deep within the star itself, while Jupiter would orbit just above its surface. And the much larger surrounding nebula would engulf all the planets and dwarf planets, even veiling some of the comets that orbit far beyond Neptune's orbit. (The outer shell of the nebula has a radius of 10,000 times the distance from the Earth to the sun.)
"This object was known to glow brightly in the infrared but, surprisingly, nobody had identified it as a yellow hypergiant before," said Eric Lagadec, of the European Southern Observatory, who led the team that produced the new images, in a statement.
Yellow hypergiants like this one are in an extremely active phase of their life cycle, undergoing a series of explosive events. In fact, this star has ejected four times the mass of the sun in just a few hundred years, with that ejected matter forming the nebula's double shell. The explosions signal a nearing death for the star, which the researchers will be one of the next supernova explosions in our galaxy. Toast anyone?
Shattered Star Sends Mysterious Signal
The pulsed gamma rays have energies between 100 billion and 400 billion electronvolts, far higher than the 25 billion electronvolts previously detected. A 400 billion electronvolt photon is almost a trillion times more energetic than the photons that make up visible light. Explaining this high energy is going to require major adjustments to astronomers' theories of the energy interactions in the nebula.
"The finding shows that the theory is not there yet," said study researcher Henric Krawczynski, a professor of physics at Washington University in St. Louis. "We know less about these systems than we thought."
Dashing Draconid Caught on Film
View From Another World
A recent Harvard-Smithsonian Center for Astrophysics study finds that dark matter is distributed smoothly throughout dwarf galaxies, contradicting scientists' expectations that the dark matter would be clustered at the center of these galaxies like a pit in a peach. These findings suggest that scientists are missing something in their understanding of dark matter's mysteries.
An Old Explosion Shines Bright
The supernova, known as RCW 86, was recorded by Chinese astronomers in 185 A.D. Today, astronomers use space telescopes to peer at the debris RCW 86 left behind. This image was stitched together with data from four space telescopes; the blue and green colors only show up on x-ray images. These x-rays show interstellar gas that has been heated to millions of degrees by the passage of the shock wave from the supernova. The red represents dust at a temperature of several hundred degrees below zero — cold to human senses, but quite warm compared to typical space dust in our Milky Way galaxy.
Galaxies Masquerade as Eyes in the Sky
Galaxies NGC 2207 and IC 2163 met and began a slow gravitational merge about 40 million years ago. This false-color image of the galaxies shows their cores in blue-green and their spiral arms in bright red. Eventually, the two galaxies will become one.
Shocking Space Spider
These supernova explosions and stellar winds form "shock fronts," which are similar to sonic booms. Multimillion-degree gas from these shock fronts is visible in blue in this Chandra X-ray Observatory and Spitzer Space Telescope image. The hot gas carves out bubbles in the surrounding cooler gas, shown here in orange.
Solar flares are bursts of electromagnetic energy and particles that sometimes stream from the sun. Flare activity fluctuates in a 11-year cycle, which is currently ramping up. Some 2012 doomsday predictors, anxieties piqued by the upcoming end of the ancient Mayan long-count calendar, believe that peak solar flare activity in 2012 will spell the end for us all. But according to NASA, these doom-sayers are way off base. For one thing, the next solar flare maximum won't even occur in 2012; it's likely to hit in late 2013 or early 2014.
But more importantly, there's nothing particularly special about the next solar maximum. According to NASA, electromagnetic radiation from solar weather can disrupt satellite transmission, and in extreme cases, power grids, but precautions by satellite operators and electric companies can prevent problems. And counter to any "the world will end in fire" predictions, the sun doesn't have enough energy to send a solar flare 93 million miles to Earth, the space agency reports. As the above solar flare image reveals, we've all lived through solar maximums before and lived to tell the tale.
Stormy, Stormy Saturn
In this false-color image, red and orange indicate clouds that are low in the atmosphere, while yellow and green are intermediate clouds. White and blue are high clouds and haze. The rings of the planet appear as a thin, bright blue line. The darkness in the lower left of the image is the shadow cast by Saturn's moon, Enceladus.
Tie-Dyed Asteroid Vesta
Color data obtained by the framing camera aboard NASA's Dawn spacecraft was used to show asteroid Vesta's southern hemisphere in a rainbow-colored palette. Colors were assigned based on the ratios of two wavelengths of radiation detected by the framing camera.
The shot is centered on the Rheasilvia formation, which is an impact basin that measures about 290 miles (467 kilometers) in diameter. Scientists used the colors to illustrate the asteroid's different rock and mineral types. For example, green suggests the presence of the iron-rich mineral pyroxene or large-sized particles.
The photo is actually a mosaic, composed of images taken while the Dawn spacecraft approached Vesta. The black hole in the middle is where data was omitted due to the angle between the sun, Vesta and the spacecraft.
Blood-Red Moon Eclipse
Early Saturday morning (Dec. 10), a total lunar eclipse will cast the moon into shadow and make it appear bright red. Skywatchers in western Canada and the United States should have a great view of the eclipse, which will start at 7:45 a.m. EST (4:45 a.m. PST, 1245 GMT).
Observers in Australia, New Zealand, and central and eastern Asia should also have a good view of the total lunar eclipse, which occurs when the Earth passes between the sun and the moon, throwing the moon into shadow.
The above stunning shot, taken by skywatcher George Tucker, is of a lunar eclipse observed on June 15, 2011. The photo was taken from the Sossusvlei Desert Lodge on the NamibRand Nature Reserve located in Namibia, a country in southern Africa.
Amazing Glowing Hourglass
Puppis A formed when an massive star died with a bang, sending out a shock wave that heated the surrounding dust and gas clouds, seen here in red. Some of the green gas in this image is from yet another ancient supernova, the Vela supernova. That explosion is about three times older the Puppis A, but four times closer to Earth.
Love, Joy & a Happy New Year
Astronomers were shocked, but Lovejoy continues to put on a show. On Dec. 22, ESO astronomer Gabriel Brammer took this early-morning shot of Lovejoy set against the backdrop of the Milky Way, long tail of dust particles streaming behind it. The comet continues its orbit around the sun; if it survives, it will reappear in our skies in 314 years.
This artist's concept illustrates what scientists say is the fastest rotating star found to date. Called VFTS 102, the massive, bright young star rotates at a million miles per hour, or 100 times faster than our sun does. Centrifugal forces from this dizzying spin rate have flattened the star into an oblate shape and spun off a disk of hot plasma, seen edge-on in this view from a hypothetical planet. The star may have "spun up" by accreting material from a binary companion star, according to the scientists involved. The rapidly evolving companion later exploded as a supernova. The whirling star lies 160,000 light-years away in the Large Magellanic Cloud, a satellite galaxy of the Milky Way.
This image, captured at 14:14 Universal Time on Jan. 24 (9:14 a.m. EST}, shows our stormy sun. The sun goes through 11-year cycles of activity and is currently ramping up. Fears that these solar storms could trigger apocalypse on Earth, however, are overblown.
Can you guess what a black hole eats for dinner? A team of scientists may have just found a clue. They had wondered about the source of mysterious X-ray flares in the region of a supermassive black hole at the center or our galaxy called Sagittarius A*, or Sgr A*. A cloud around Sgr A* contains hundreds of trillions of asteroids and comets, which have been stripped from their parent stars. The flares occur when the black hole consumes asteroids having a radius of 6 miles (nearly 10 kilometers) or larger, they found.
If the asteroid passes within about 100 million miles (161 million kilometers) of the black hole, roughly the distance between the Earth and the sun, it is torn into pieces by the tidal forces from the black hole. These fragments would then be vaporized by friction as they pass through the hot, thin gas flowing onto Sgr A*, similar to a meteor heating up and glowing as it falls through Earth's atmosphere. A flare is produced and eventually the remains of the asteroid are swallowed by the black hole.
The next partial solar eclipse Earthlings will be able to see will occur May 20, with views visible from Asia, the Pacific and western North America.
Dust and Lace in Space
Cotton Candy Sun
This false-color image combines all of STEREO's wavelengths into one picture, enabling scientists to compare different features and wavelengths. The goal of the project is to better understand the physics of the sun, thus enabling scientists to more accurately predict space weather.
Alien Dust Devil!
The rusty soil probably gave it away: It's Mars. The High Resolution Imaging Science Experiment (HiRISE) is a camera aboard the Mars Reconnaissance Orbiter,which sends back ultra-high-resolution images of the surface of Mars. HiRISE caught this alien twister scouring the dusty Martian surface in the late Martian spring. Researchers calculate that the dust plume reached 2,625 feet (800 meters) high. Martian winds blew the plume out toward the east as the dust devil itself headed southeast.
Stunning Sun Storm
There are three classifications of solar flares, based on x-ray brightness. X-class is the most intense, followed by M- and C-class flares. This flare, shown in a teal-colorized wavelength, is an M-class flare.
Glitter at the Center of the Galaxy
Blowing Smoke Rings at the Edge of Space
On March 27, NASA successfully launched five suborbital rockets in order to study the upper level jet stream. Each rocket, launched one after another 80 seconds apart, released a chemical tracer to create these milky clouds at the very edge of space, 65 miles (105 km) up.
Tracking the movements of the clouds will help researchers understand air movements at this level of the atmosphere. Meanwhile, these enormous cloud rings were visible as far south as Wilmington, N.C. and as far north as Buffalo, N.Y.
Galactic Easter Egg
The 'rings' of this galaxy are the aftermath of a collision between the Cartwheel galaxy and another galaxy about 100 million years ago. The first ripple is the blue outer ring, while the yellow-orange "yolk" of the Easter egg is a combination of visible and infrared light from the second ripple. The neon blob and green spiral in the background are two other galaxies, one of which may have been the one that collided with Cartwheel
Zooming in on Saturn's Rings
Technicolor Tarantula Nebula
This image is a composite, with x-ray energy seen by the Chandra X-ray Observatory visible in blue, light seen by Hubble in green and infrared emissions captured by the Spitzer observatory in red. The x-rays are caused by sonic-boom-like shock waves associated with stellar activities, the light is emitted by stars of different ages, and the infrared emissions represent relatively cool gas and dust.
Two Galaxies for the Price of One
The alienlike beauty of this image, taken by a camera aboard NASA's Mars Reconnaissance Orbiter (MRO), may seem to portend some Martian artists. Alas, the ridges and ripples are evidence of Martian sand dunes. The brighter features represent two classes of so-called aeolian bedforms within Proctor Crater. The ripples, research has shown, are composed of fine sand or fine sand coated with coarser sand and granules. And the larger, darker bedforms are dunes composed of sand, possibly derived from basaltic, or volcanic, rock (and hence the darker color). Ripples tend to move slower than dunes. Because of this, over time, ripples get covered with dust, possibly explaining the bright tone visible here. The image was taken by the MRO's High Resolution Imaging Science Experiment (HiRISE) on Feb. 9, 2009.
Setting Solar Eclipse
Glow Stick Sun
Birthing Stars in War & Peace
The War and Peace Nebula got its name because scientists on the Midcourse Space Experiment thought that one half of the nebula looked like a dove, while the other half looked like a skull. That effect isn't visible in this newest image.
Saturn's Jet Stream
Camelopardalis, or U Cam for short, is a star nearing the end of its life. As stars run low on fuel, they become unstable. Every few thousand years, U Cam coughs out a nearly spherical shell of gas as a layer of helium around its core begins to fuse. The gas ejected in the star's latest eruption is clearly visible in this picture as a faint bubble of gas surrounding the star. U Cam is an example of a carbon star, a rare type of star with an atmosphere that contains more carbon than oxygen. Due to its low surface gravity, typically as much as half of the total mass of a carbon star may be lost by way of powerful stellar winds. Located in the constellation of Camelopardalis (The Giraffe), near the North Celestial Pole, U Cam itself is much smaller than it appears in this Hubble image. In fact, the star would easily fit within a single pixel at the center of the image. Its brightness, however, is enough to saturate the camera's receptors, making the star look much larger than it is.
The shell of gas, which is both much larger and much fainter than its parent star, is visible in intricate detail in Hubble's portrait. This phenomenon is often quite irregular and unstable, but the shell of gas expelled from U Cam is almost perfectly spherical.
It's much more appealing, though it is gassy. … This true color image captured by NASA'S Cassini spacecraft before a distant flyby of Saturn's moon Titan on June 27, 2012, shows a south polar vortex, or mass of swirling gas, in the moon's atmosphere. The vortex seems to complete one full rotation in nine hours, while Titan takes about 16 days to spin once around its axis.
The vortex, which is swirling at a high altitude could be a response of Titan's stratosphere to seasonal cooling as the southern winter nears, according to NASA scientists. "Polar vortexes have also been observed on Saturn, Jupiter, Neptune, Earth and Venus, scientists say. [Read the full story]
Green Eggs and Ham?
From the Hip
Whirlpool of Stars
Stars die here, too. Astronomers have spotted two supernovas, or explosions caused by the death of a star or white dwarf, in NGC 1187. The second, dubbed SN 2007Y for the year it was first spotted, can be seen as a bright spot near the bottom of this image.
Approaching the Red Planet
On that day, years of preparation will culminate in what scientists call "7 minutes of terror" on Sunday. That's the amount of time it takes the rover-carrying spacecraft to get from the top of Mars' atmosphere to its surface. But because it takes 14 minutes for the signal from the spacecraft to reach Earth, by the time NASA scientists hear that the spacecraft has hit the atmosphere, it's actually been on the surface for 7 minutes. Until those 7 minutes pass, no one will know whether the rover made it down safely.
The Curiosity rover's mission is to study Mars' climate and geology, as well as to gather information for a potential manned mission to Earth's neighboring planet.
Rover's First Look at Mars
This image is at one-quarter of full resolution. Curiosity is set to start sending back high-resolution and color images later this week.
Dazzling Diamond Collision
Up Close on Mars
The rock, dubbed "Bathurst Inlet," is so fine-grained that the Imager cannot see individual grains. A few grains of sand and dust rest on top of the rock, but it is much cleaner than the dusty substrate around it.
Eye in the Sky
The brilliant purple at the center of this stellar "eye" is the ultraviolet and infared glow of dust surrounding the white dwarf. This dust is the remnants of outer planets and comets that might have once orbited this star. In 5 billion years or so, our solar system will face a similar fate.
Crazy Cat's Eye
This image is part of a recent study published August 2012 in The Astronomical Journal examining 21 planetary nebulas within 5000 light-years of our own planet. Despite their name, planetary nebulas are not planets, but dying stars that have used up their hydrogen cores and expanded. Our own sun will become a planetary nebula in several billion years.
Catch a Falling Star
Our Violent Sun
Tracking a Storm on Saturn
Private Solar Eclipse
Stunning Storm Swirls on Saturn
"These phenomena mimic what Cassini found at Saturn's south pole a number of years ago," Cassini scientists wrote in an online update.
The image was snapped Nov. 27, 2012, and received on Earth the same day, though it has yet to be validated or calibrated, according to NASA.
Launched in 1997 and arriving on the planet in July 2004, Cassini is the first spacecraft to orbit Saturn. The probe has logged more than 3.8 billion miles (6.1 billion kilometers), along the way making major discoveries about the Saturn system, including finding the presence of hydrocarbon lakes on its moon Titan and spewing water geysers on the moon Enceladus.
Cosmic Glow Ball
Three bands, or portions of the spectrum, were used to create the ghostly image above. Breaking down the northern lights in this way allows researchers to see subtle atmospheric changes. Already, the researchers report Nov. 29, 2012 in the journal Optics Express, the technique may have revealed a strange phenomenon called airglow, in which Earth's atmosphere emits its own light through electromagnetic or chemical reactions. If the finding holds, it will be the first known observatio of airglow associated with an aurora.
Not quite. That little speck is Tethys, one of Saturn's moons. The moon is 660 miles across (1,602 km), but with Saturn in the foreground, it doesn't show its size. The Cassini spacecraft took this image in August 2012 from about 18 degrees below the plane of Saturn's rings.
CMEs and other solar activity are currently in the news because some believers in the so-called Mayan Apocalypse think that sun activity is set to destroy or damage Earth on Dec. 21. In fact, according to NASA, the sun is showing no signs of unusual activity.
Last Men on the Moon
A Star is Born
Shiny, Shiny Space
The Hubble Space Telescope captured this image of NGC 5189. Despite the "planetary nebula" moniker, this gas cloud comes not from a planet, but from a star. A planetary nebula is the final stage of life of medium-sized stars. As the star consumes the last of its fuel, it expels its outer envelope, which becomes heated, creating the glowing gas clouds seen here.
The Heart of a Galaxy
Using data from the Hubble and Spitzer space telescopes, NASA scientists created this striped image of the brown dwarf, revealing stormy layers of gases in the atmosphere. The results were presented Jan. 8 at the annual meeting of the American Astronomical Society in Long Beach, Calif.
The star TW Hydrae is surrounded by its disk of gas and dust, as shown in this artist's depiction. Scientists have just found the mass of this disk, which is regarded as a prototypical example of planetary nurseries, is greater than was previously assumed. They reported the finding in the Jan. 31, 2013, issue of the journal Nature.
Using the Herschel Space Telescope, the scientists set a new lower limit for the disk's mass at 52 Jupiter masses. The finding suggests that even in a relatively old stellar system like TW Hydrae (estimated to be between 3 million and 10 million years old), there is still ample matter in the disk to form a planetary system larger than our own. TW Hydrae is just 176 light-years from Earth.
The Colorful Side of the Moon
This is a view of the dark side the moon, an angle never visible from Earth. Satellites orbiting the moon do get this view, however, and can measure gravity variations from orbit.
A Cloudy Space Mystery
This hexagonal cloud formation, first discovered in the 1980s by the Voyager spacecraft, was photographed again in 2012 by the Cassini spacecraft. The formation sits at Saturn's north pole; it's visible here in the foreground with a portion of Saturn's rings looping around in the upper right-hand corner of the image. No one knows why clouds form in this geometrical pattern in this region of Saturn.
The purpose of the LAT is to capture gamma ray light from our own galaxy, as well as from objects (such as supermassive black holes) billions of light-years away, according to NASA.
The Hubble observatory, which launched on April 24, 1990, captured the Horsehead Nebula (also known as Barnard 33) rising like a giant seahorse from the turbulent waves of gas and dust in this stunning infrared light image. "The result is a rather ethereal and fragile-looking structure, made of delicate folds of gas — very different to the nebula’s appearance in visible light," mission officials wrote in an image description Friday (April 19).