Nell Greenfieldboyce

Pluto is the only place other than Earth in our solar system that's known to have white-peaked mountains, but these white caps aren't made of snow.

Instead, they're made of methane frost. And, according to a new report in the journal Nature Communications, these alien mountains get their peaks whitened in a way that's totally unlike what occurs on Earth's summits.

The Nobel Prize in chemistry was awarded this year to Emmanuelle Charpentier and Jennifer Doudna for their work on "genetic scissors" that can cut DNA at a precise location, allowing scientists to make specific changes to specific genes.

Giant flares and eruptions from the sun can cause space weather, and stormy space weather can interfere with everything from satellites to the electrical grid to airplane communications. Now, though, there's good news for people who monitor the phenomenon — the sun has passed from one of its 11-year activity cycles into another, and scientists predict that the new cycle should be just about as calm as the last.

Scientists say they've detected a gas in the clouds of Venus that, on Earth, is produced by microbial life.

The researchers have racked their brains trying to understand why this toxic gas, phosphine, is there in such quantities, but they can't think of any geologic or chemical explanation.

The mystery raises the astonishing possibility that Venus, the planet that comes closest to Earth as it whizzes around the sun, might have some kind of life flourishing more than 30 miles up in its yellow, hazy clouds.

Mike Brown has been using the Hubble Space Telescope pretty consistently for most of the past three decades since it launched in 1990. But recently he had an experience with Hubble that he never had before.

With the annual flu season about to start, it's still unclear exactly how influenza virus will interact with the coronavirus if a person has both viruses.

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Water is everywhere on Earth - the clouds, the rain, the oceans and rivers, even our own bodies. Where all that water originally came from is a bit of a mystery. NPR's Nell Greenfieldboyce reports that scientists may have found the answer inside some rare meteorites.

Water on Earth is omnipresent and essential for life as we know it, and yet scientists remain a bit baffled about where all of this water came from: Was it present when the planet formed, or did the planet form dry and only later get its water from impacts with water-rich objects such as comets?

This year's flu season in the Southern Hemisphere was weirdly mild.

A surprisingly small number of people in the Southern Hemisphere have gotten the flu this year, probably because the public health measures put in place to fight COVID-19 have also limited the spread of influenza.

That makes public health experts hopeful that the U. S. and other northern countries might be spared the double whammy of COVID-19 and a bad flu season this winter.

Still, they warn against complacency and say people still need to get vaccinated against the flu.

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When a weather station in Death Valley, Calif., registered an astonishing 130 degrees Fahrenheit this week, it got meteorologists' attention.

After all, there's a possibility that this is the highest such temperature ever reliably recorded on Earth — if it's for real.

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A steel razor blade can get dull surprisingly quickly when cutting something as soft as hair, and now researchers have gotten their first up-close look at how a close shave actually damages an everyday disposable razor.

This leading-edge research, described in the journal Science, used a scanning electron microscope to peer at a razor as it sliced through strands of hair.

Updated at 6:40 p.m. ET

Two NASA astronauts are back on Earth after their space capsule splashed down in the Gulf of Mexico, off the coast of Pensacola, Fla.

The last time any NASA astronauts came home by splashing down was in 1975 — and back then, they were in an Apollo space vehicle. This time, the astronauts were in a white, bell-shaped capsule owned by SpaceX.

Updated 7:30 p.m. ET Saturday

The two astronauts that blasted off in the first private space vehicle to take people to the International Space Station are about to return to Earth — by splashing down in the waters around Florida.

This will be the first planned splashdown for space travelers since 1975, although a Russian Soyuz capsule did have to do an emergency lake landing in 1976.

The first genetically altered squid has scientists excited about a potential new way to study marine critters that are so weird, they've sometimes been compared to alien life forms.

A mosquito that transmits dangerous viruses like dengue and Zika seems to have developed a taste for human blood because of the way that people store water — which mosquitoes need for laying eggs — in hot, dry climates.

That's according to a new study in Current Biology that tested the biting preferences of Aedes aegypti populations from 27 locations across sub-Saharan Africa, the ancestral home of this mosquito species.

Rats will enthusiastically work to free a rat caught in a trap — and it turns out that they are especially eager to be a good Samaritan when they're in the company of other willing helpers.

But that urge to come to the rescue quickly disappears if a potential hero is surrounded by indifferent rat pals that make no move to assist the unfortunate, trapped rodent.

Flying snakes like Chrysopelea paradisi, the paradise tree snake, normally live in the trees of South and Southeast Asia. There, they cruise along tree branches and, sometimes, to get to the ground or another tree, they'll launch themselves into the air and glide down at an angle.

They undulate their serpentine bodies as they glide through the air, and it turns out that these special movements are what let these limbless creatures make such remarkable flights.

Dolphins learn special foraging techniques from their mothers—and it's now clear that they can learn from their buddies as well. Take the clever trick that some dolphins use to catch fish by trapping them in seashells. It turns out that they learn this skill by watching their pals do the job.

The discovery, reported in the journal Current Biology, helps reveal how groups of wild animals can transmit learned behaviors and develop their own distinct cultures.

In 2018, paleontologist Julia Clarke was visiting a colleague named David Rubilar-Rogers at Chile's National Museum of Natural History. He showed her a mysterious fossil that he'd collected years earlier in Antarctica. He and his co-workers called it "The Thing."

"It was weird enough that they decided to collect it, even though it wasn't clear what it was. It definitely wasn't bone, but it was strikingly unusual," recalls Clarke, who works at the University of Texas at Austin.

Sea otter populations are rebounding in the eastern North Pacific. There, they devour huge quantities of shellfish and other marine critters that people like to eat, too. But any commercial losses to fisheries are far outweighed by economic benefits associated with the otters, according to a new study.

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Shortly after NASA astronauts blasted off from U.S. soil for the first time since 2011, President Trump painted a dire picture of what the space agency had looked like when he first came to office.

"There was grass growing through the cracks of your concrete runways — not a pretty sight, not a pretty sight at all," he said at NASA's enormous Vehicle Assembly Building at Kennedy Space Center in Florida, where he had come to watch two astronauts launch to orbit in a vehicle owned and operated by SpaceX.

Almost 40 years have passed since the last time NASA astronauts blasted off into space on a brand new spaceship.

Now, as NASA looks forward to Wednesday's planned test flight of the SpaceX Crew Dragon with a pair of astronauts on board, some in the spaceflight community have a little bit of déjà vu.

In 2006, while hiking around the Root Glacier in Alaska to set up scientific instruments, researcher Tim Bartholomaus encountered something unexpected.

"What the heck is this!" Bartholomaus recalls thinking. He's a glaciologist at the University of Idaho.

NASA's head of human spaceflight has abruptly resigned just one week before a historic test flight to send astronauts up in a new space capsule developed by the rocket company SpaceX.

The unexpected departure of Doug Loverro startled the space community, which has been looking forward to launching astronauts from U.S. soil for the first time since the space shuttles stopped flying in 2011.

The White House has touted the fact that its coronavirus task force provided each state with a list of labs that could potentially test for the virus, but officials in a number of states told NPR that the lists did not actually help them increase testing.

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