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NASA is at a critical juncture in its push to get people back to the moon by 2024, with key decisions expected within weeks.

This effort to meet an ambitious deadline set by the Trump administration last year faces widespread skepticism in the aerospace community, even as the new head of human spaceflight at NASA insists that it can succeed.

U.S. officials are weighing the benefits and risks of proposed experiments that might make a dangerous pathogen even worse — but the details of that review, and the exact nature of the experiments, aren't being released to the public.

Later this week, officials are to hold a meeting in Bethesda, Md., to debate how much information to openly share about this kind of controversial work and how much to reveal about the reasoning behind decisions to pursue or forgo it.

Some wolf puppies are unexpectedly willing to play fetch, according to scientists who saw young wolves retrieve a ball thrown by a stranger and bring it back at that person's urging.

This behavior wouldn't be surprising in a dog. But wolves are thought to be less responsive to human cues because they haven't gone through thousands of years of domestication.

Parrots can perform impressive feats of intelligence, and a new study suggests that some of these "feathered apes" may also practice acts of kindness.

African grey parrots voluntarily helped a partner get a food reward by giving the other bird a valuable metal token that could be exchanged for a walnut, according to a newly published report in the journal Current Biology.

An enormous number of tumbleweeds blew onto a road in eastern Washington state on New Year's Eve, piling up into a mountain of tangled branches that blocked traffic and even buried some cars, trapping travelers inside.

"In the 20 years that I have worked here, I have never seen it as bad as this," says Washington State Patrol trooper Chris Thorson. "I've never seen six to eight cars, including a semi-truck, actually stopped and trapped on a highway because of tumbleweeds."

Shepherds in Christmas Nativity scenes that were painted, carved or sculpted hundreds of years ago sometimes have throats with large, abnormal growths.

These are realistic depictions of goiter, an enlargement of the thyroid gland caused by iodine deficiency. The condition was common in those days in northern Italy, where the soil and water are depleted of iodine.

Steamboat Geyser, the tallest active geyser in the world, erupted more times in 2019 than in any other year, baffling scientists who are trying to understand what triggered this unusual streak of activity.

The geyser can shoot water more than 300 feet into the air, and this year it has erupted more than 45 times, surpassing the 32 eruptions recorded in 2018.

The Department of Labor's workplace safety agency is getting ready to take new action to reduce workers' exposure to dangerous silica dust that can irreparably damage the lungs.

Every day, 20 to 30 trucks roll into a factory in Minnesota. They're filled with quartz — some of it like a powder, and some of it like sparkling little pebbles, in big white sacks.

Vampire bats might have a nasty reputation because of the way they ruthlessly drink their victims' blood, but these bloodthirsty beasts can be both generous and loyal when it comes to their fellow bats.

Captive common vampire bats will share their food with hungry bat companions, and forge such a bond that they continue to hang out with these buddies once they're released back to the wild, according to a newly published study in the journal Current Biology.

Lawmakers in Congress are calling on the Department of Labor to do more to protect workers who may be unsafely cutting "engineered stone" used for countertops.

The material contains high levels of the mineral silica, and breathing in silica dust is dangerous. While silica is found in natural stones, like granite, engineered stone made of quartz can be more than 90% silica.

Artificial stone used to make kitchen and bathroom countertops has been linked to cases of death and irreversible lung injury in workers who cut, grind and polish this increasingly popular material.

The fear is that thousands of workers in the United States who create countertops out of what's known as "engineered stone" may be inhaling dangerous amounts of lung-damaging silica dust, because engineered stone is mostly made of the mineral silica.

An oddball solar system discovered not too far from our own is forcing astronomers to reexamine their ideas about how planets get created.

In the journal Science, researchers report they detected a small, dim red dwarf star, about 30 light-years from Earth, being tugged by the gravity of what must be a huge, Jupiter-like planet.

Patrick Boyle recalls that by the time he got his Ph.D. in biology in 2012, he had worked with just a few other people and managed to manufacture six genes, the basic units of heredity.

"Today, we are synthesizing more than 10,000 genes every month," he says, showing off a lab at a Boston biotech company called Ginkgo Bioworks.

Over the past half-century, North America has lost more than a quarter of its entire bird population, or around 3 billion birds.

That's according to a new estimate published in the journal Science by researchers who brought together a variety of information that has been collected on 529 bird species since 1970.

The next generation of doctors will start their careers at a time when physicians are feeling pressure to limit prescriptions for opioid painkillers.

Yet every day, they'll face patients who are hurting from injuries, surgical procedures or disease. Around 20% of adults in the U.S. live with chronic pain.

The Environmental Protection Agency says it will aggressively reduce the use of animals in toxicity testing, with a goal of eliminating all routine safety tests on mammals by 2035.

Chemicals such as pesticides typically get tested for safety on animals like mice and rats. Researchers have long been trying to instead increase the use of alternative safety tests that rely on lab-grown cells or computer modeling. The EPA's administer, Andrew Wheeler, has now set some specific deadlines to try to speed up that transition.

Squirrels eavesdrop on the casual chitchat of birds to figure out when it's safe enough to be out in the open and foraging for food.

Researchers have found that a squirrel becomes incredibly vigilant when it hears the shriek of a red-tailed hawk, but it will relax and resume its food-seeking behavior more quickly if the predator's call is immediately followed by the easygoing tweets of unconcerned birds.

A few years ago, TV celebrity Rachel Maddow was at Rockefeller University to hand out a prize that's given each year to a prominent female scientist. As Maddow entered the auditorium, someone overheard her say, "What is up with the dude wall?"

She was referring to a wall covered with portraits of scientists from the university who have won either a Nobel Prize or the Lasker Award, a major medical prize.

Science has some bad news for the bearded: young children think you're really, really unattractive.

A new study suggests that, until they reach puberty, kids are strongly anti-beard — although children with bearded fathers did feel more warmly toward facial hair.

Ocean-dwelling sharks often like to hang out in areas that also get frequented by industrial fishing ships, which puts them at grave risk of being caught either for food or as bycatch.

That's according to a new study in the journal Nature that mapped the activity of 23 shark species and fishing vessels around the globe.

When a rocket carrying the first module of the International Space Station blasted off from Kazakhstan in November of 1998, NASA officials said the station would serve as an orbiting home for astronauts and cosmonauts for at least 15 years.

Mike Morrison hardly looks like a revolutionary. He's wearing a dark suit and has short hair. But we're about to enter a world of conformity that hasn't changed in decades — maybe even a century. And in there, his vision seems radical.

"We are about to walk into a room full of 100 scientific posters, where researchers are trying to display their findings on a big poster board," says Morrison, a doctoral student in psychology at Michigan State University.

At the Marine Biological Laboratory in Woods Hole, Mass., there's a room filled with burbling aquariums. A lot of them have lids weighed down with big rocks.

"Octopuses are notorious for being able to, kind of, escape out of their enclosures," says Bret Grasse, whose official title at MBL is "manager of cephalopod operations" — cephalopods being squid, cuttlefish and octopuses.