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A small rock might contain tissue from a 130 million-year-old dinosaur brain. If confirmed, it would be the first bit of fossilized dino gray matter ever found.

When astronomers spot a new planet that's too far away to be seen in detail, they work with artists to depict it. Space artists say they have a lot of freedom, but have to be careful, too.

In tight elections, the loser often calls for a recount. But recounting ballots might not be easy in states that use paperless machines — including the presidential battleground state of Pennsylvania.

President Obama has once again declared that humans should go to Mars by the 2030s. NPR looks back on his eight years in office to see whether he's put NASA on track to get there.

To cap its 12-year scientific voyage, the Rosetta spacecraft will take a final plunge Friday. Scientists will signal Rosetta to crash into the surface of a comet — and gather data all the way down.

If jets of water vapor are indeed erupting from Europa, a spacecraft could potentially fly through them and analyze their chemistry. The moon is believed to have a vast subterranean, saltwater ocean.

Blobs in space emitting eerie, unexplained light have been puzzling astronomers for more than 15 years. Now, they think they are on to the cause of the mysterious glow.

Flying people to an asteroid is really hard, so NASA wants to bring part of it to them. But some former astronauts say the $2 billion plan was born of politics and budget cuts, and makes little sense.

The National Marine Fisheries Service says nine of the 14 distinct populations of humpback whales have recovered enough that they no longer need to be considered endangered.

Scientists knew that lizards, which bask in the sun for warmth, are vulnerable to climate change. A new study suggests the hazards are more complicated, and possibly worse, than previously believed.

When humans talk to dogs, the canine brains seem to separate the meaning of the words from the intonation used and to analyze each aspect independently.

It's not exactly close — 25 trillion miles from Earth, say the scientists who spotted it. But that might be near enough for further exploration. It's about Earth's size, with mild temperatures.

You may love or hate "the wave" as it sweeps through spectators at baseball, football and soccer games. But physicists say the synchronized action shows how humans are like particles.

This Arctic species can live longer than any other known animal advanced enough to have a backbone, scientists say — maybe more than 500 years. Their muscles might hold clues that could help humans.

The popular annual Perseid meteor shower peaks Thursday night. If astronomical predictions hold true, it could be the best show in years.

Nighttime driving restrictions on teens may save lives, a study finds, but should probably be shifted to include late evening. A third of all fatal crashes with teen drivers happen after dark.

A mysterious fireball seen in the sky over the American West on Wednesday night turned out to be Chinese rocket falling through the atmosphere.

Think summer's hot on Earth? Space physicists tracking weather on Jupiter say the roar of the raging storm we call the Great Red Spot heats the outer atmosphere above it by more than 1,000 degrees F.

It sounds like a fairy tale but it's real. A study shows how wild birds and people communicate to find bees' nests and share the sweet honeycomb. The teamwork may date back thousands of years or more.

Scientists who have been tracking cloud patterns over the past two decades say the shifts they're seeing seem to correlate closely with what's predicted by computer models of Earth's changing climate.