Each week at Live Science we find the most interesting and informative articles we can. Along the way, we uncover some amazing and cool images. Here you'll discover the most incredible photos we found this week, and the remarkable stories behind them.
A 'Wall' of matter in the southern sky
Spectacular 3D maps of the universe have revealed one of the biggest cosmic structures ever found — an almost-inconceivable wall stretching 1.4 billion light-years across that contains hundreds of thousands of galaxies.
The South Pole Wall, as it's been dubbed, has been hiding in plain sight, remaining undetected until now because large parts of it sit half a billion light-years away behind the bright Milky Way galaxy — a region called the Zone of Galactic Obscuration. By measuring the velocity of galaxies hidden in this zone, the authors of a new study calculated approximately how much matter was lurking there.
The resulting map shows a mind-boggling bubble of material more or less centered on the southernmost point of the sky, with a great sweeping wing extending north on one side in the direction of the constellation Cetus and another stubbier arm opposite it in the direction of the constellation Apus. What's more, this massive structure may be even larger than it seems; "We will not be certain of its full extent, nor whether it is unusual, until we map the universe on a significantly grander scale," the researchers wrote.
[Read more: Astronomers discover South Pole Wall, a gigantic structure stretching 1.4 billion light-years across]
A red mine in the abyss
At the end of the last ice age, Indigenous miners in what is now the Yucatan Peninsula, Mexico risked life and limb — venturing into pitch dark caves illuminated only by fire — to extract a prized mineral, a new study finds. That mineral wasn't gold or diamonds, but red ochre, a valuable crayon-like pigment that prehistoric people used for both ritualistic and everyday activities, including rock paintings, burials and possibly even insect repellent.
Cave divers discovered the ancient mining camps in April 2017 after following a previously undocumented passageway. The underwater passageway led the divers to a spectacular array of ice age mining artifacts, including tools, mining pits and stone markers, likely left so the miners wouldn't get lost in the dark labyrinth.
After Indigenous people mined the caves, between about 12,000 and 10,000 years ago, the caves flooded as the ice age ended and sea levels rose. But the still water in the caves preserved the miners' camps — even the charred remains of their fires — allowing archaeologists to see exactly how the mineral was extracted.
[Read more: Ice age mining camp found 'frozen in time' in underwater Mexican cave]
Pachyderms in the dust
More than 350 elephants in Botswana have mysteriously died since May, in a phenomenon that some scientists have dubbed a "conservation disaster," and one that has evaded explanation.
The elephants — which died in the swampy Okavango Delta — still had their tusks intact, suggesting that ivory poaching hadn't driven the deaths, The Guardian reported. A flight over the delta in May by researchers with Elephants Without Borders, a wildlife conservation organization, first spotted 169 carcasses; that number jumped to 356 in June, when the conservationists took another flight over the area.
The mass die-off could be explained by either a poison or some as-yet unknown pathogen, according to The Guardian. Local sources told The Guardian that 70% of the elephant carcasses — which span all ages — have been found around watering holes, so perhaps the culprit is somehow linked to watering holes, The Guardian reported. Also, locals have reported that some of the elephants were walking in circles before their deaths, suggesting a neurological issue.
[Read more: 350 elephants drop dead in Botswana, some walking in circles before doing face-plants]
Walking through watermelon snow
A pink invader is threatening Italy's massive Presena glacier. The Alpine glacier, once the site of World War I battles between the Kingdom of Italy and the Austro-Hungarian Empire and now an outdoor and skiing destination, seems to have caught a bad case of "watermelon snow," according to a CNN report.
The pink hue comes from algae growing on the ice. Though the itty-bitty algae doesn't damage the glacier directly, it makes the normally white surface darker, allowing it to absorb more light from the sun. That absorbed light heats the glacier, speeding up its rate of melt. At 10,068 feet (3,069 meters) above sea level, the glacier has lasted intact for millennia through the summers.
Biagio Di Mauro, a researcher at the Institute of Polar Sciences at Italy's National Research Council, told CNN that the microscopic plant species Chlamydomonas nivalis likely caused the sudden pink hue. The algae is common in the Alps, but low winter snowfall seems to have combined with high spring and summer temperatures to create ideal conditions for a major bloom.
[Read more: Pink 'watermelon snow' threatens major Italian glacier]
Coughing unmasked
A dramatic new visualization shows exactly why it's a good idea to wear a face mask to prevent the spread of the new coronavirus.
Without a mask, droplets produced during coughing can travel up to 12 feet (3.7 meters), the visualization revealed, but with a mask, this distance is reduced to just a few inches in the best cases. The simulation, which was described June 30 in the journal Physics of Fluids, also reveals that some cloth masks work better than others at stopping the spread of potentially infectious droplets.
To simulate a cough, the researchers connected a mannequin's head to a fog machine (which creates a vapor from water and glycerin), and used a pump to expel the vapor through the mannequin's mouth. They then visualized the vapor droplets using a "laser sheet" created by passing a green laser pointer through a cylindrical rod. In this setup, simulated coughs appear as a glowing green vapor flowing from the mannequin's mouth.
"The visuals used in our study can help convey to the general public the rationale behind social-distancing guidelines and recommendations for using face masks," study lead author Siddhartha Verma, an assistant professor at Florida Atlantic University's College of Engineering and Computer Science, said in a statement.
[Read more: Visualization shows exactly how face masks stop COVID-19 transmission]
'Godzilla' descends on America
Each year, dust from the Sahara Desert blows off Africa and across the Atlantic, but most years that plume isn't so massive it's nicknamed "Godzilla." This June, the annual plume earned that nickname, as well as the title of the dustiest such event in the 20 years that scientists have kept records of these storms.
All told, it contained between 60% and 70% more dust than a typical one of these plumes. It also traveled farther than the annual phenomenon, called the Saharan Air Layer, typically does. This year, the atmosphere carried the plume about 5,000 miles (8,000 kilometers), according to a statement from the European Space Agency (ESA), all the way out to the Caribbean islands and the southeastern United States.
ESA watched this year's dust plume throughout the month of July using its Copernicus Sentinel-5P satellite, a crucial component of its Earth-observation fleet. The satellite is tailored to study small particles in the air, like dust and pollutants.
[Read more: Satellite sees 'Godzilla' dust plume sweep across the Atlantic Ocean]
The Parrot that beat Harvard
African grey parrots (Psittacus erithacus) can live more than 50 years, memorize dozens of words in English and, if given the chance, outsmart a flock of Harvard students in a classic Shell Game.
Well, one grey parrot can, anyway. His name is Griffin, and he is the subject of a recent study published May 6 in the journal Scientific Reports. Researchers challenged Griffin to a working memory task where he had to locate a colorful pom-pom hidden under a plastic cup after it was shuffled around a table several times (aka, the Shell Game). Meanwhile, 21 Harvard students were given the same task — and Griffin matched or outperformed them in 12 of 14 trials.
"Think about it: Grey parrot outperforms Harvard undergrads. That's pretty freaking awesome," lead study author Hrag Pailian, a postdoctoral fellow at Harvard, told The Harvard Gazette. "We had students concentrating in engineering, pre-meds, this, that, seniors, and he just kicked their butts."
To be fair, Griffin is not your average parrot. According to the study authors, the 22-year-old bird "has been the subject of cognitive and communicative studies … since his acquisition from a breeder at 7.5 weeks of age."
[Read more: This parrot beat 21 Harvard students in a classic memory game]
Corona tentacles
Cells infected with the new coronavirus grow stringy, tentacle-like arms that allow the virus to invade other cells, according to a new study. In order to better understand the virus that has killed more than 555,500 people so far this year, an international group of researchers looked at how the virus changes activity inside cells in order to invade more and more cells. They specifically analyzed how the virus can alter certain proteins in infected cells. (Proteins carry out the instructions of genes, and so protein changes could impact the actual actions of infected cells.)
In a study of more than 300 human proteins, the team took high-resolution images of infected cells revealing that the cells had grown tentacle-like protrusions called "filopodia," which contained viral proteins. Those tentacles then poke holes in nearby cells, allowing the virus to infect new cells, according to the statement.
By understanding how the virus interacts with specific proteins, scientists can take another step closer to identifying which therapeutic drugs have the best chance at defeating SARS-CoV-2.
[Read more: Coronavirus hijacks cells, forces them to grow tentacles, then invades others]
Spotting spots on Betelgeuse
The weird recent dimming of the star Betelgeuse was caused by spots that temporarily covered at least half of the enormous star's surface, a new study suggests.
Betelgeuse is a "red supergiant" 11 times more massive than our sun and 900 times wider. The star's bloated state shows that Betelgeuse is in the final stages of its life, which will end in a violent supernova explosion. And last fall, the supergiant began dimming significantly, prompting some astronomers to speculate that its dramatic death may be imminent. But Betelgeuse came out of the dimming doldrums this spring, regaining its usual brightness by May.
What caused the dimming, then? According to the new study, which examined the star in submillimeter light invisible to the human eye, Betelgeuse's dimming was associated with a drop in the mean surface temperature of around 360 degrees Fahrenheit (200 degrees Celsius). Satellite images show that this temperature dip occurred in a patchwork pattern across the star's surface, pointing to the presence of massive starspots — temporary dark, relatively cool patches on a star's surface that feature very strong magnetic fields (similar to the sunspots on Earth's sun).
[Read more: Betelgeuse's weird dimming caused by gigantic starspots]
Penguin poo bombs flying free
If the Olympics awarded medals for long-distance pooping, penguins would take home the gold.
These tubby, aquatic birds can squirt arcing jets of poop to distances nearly twice their own body length, and scientists recently calculated just how much force their tiny rectums produce in order to do so — and how far the poop can fly.
To estimate penguins' pooping prowess, researchers examined variables such as stomach pressure (P = P0+Pt), atmospheric pressure (P0 = 1013 hPa) and rectal pressure (Pt). Though Humboldt penguins stand only 28 inches (71 centimeters) tall, the scientists discovered that the birds can generate enough poo-propelling energy to send fecal "bombs" flying at speeds of nearly 5 mph (8 km/h), landing up to 53 inches (134 cm) away. This achievement would be comparable to an adult human shooting their feces to a distance of more than 10 feet (3 meters), the study authors told Live Science in an email.
[Read more: Penguins shoot 'poop bombs' more than 4 feet, incredibly important study finds]
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Originally published on Live Science.
