Adam Cole

For the past 25 years, a giant flock of purple martins has gathered in Lake Murray, S.C., in late July. This year, they didn't show up.

Socializing topped the list of stress reducers for those dealing with a great deal of stress, according to an NPR poll. Prayer, meditation, exercise and playing with pets were also common responses.

A clever photography trick allows you to see the invisible: the rising heat from a lighter, the turbulence around airplane wings, the plume of a sneeze ... and even sound waves.

This winter's unexpected arctic bird invasion has given owl researchers a rare opportunity. They're fitting a few of the errant owls with GPS backpacks to track their return to the Arctic.

Long before it fueled moviegoers, popcorn helped lay the foundation for the Aztec empire. In our video, we look at popcorn under a microscope, where the rock-hard kernel's fluffy secret is revealed.

Secrets of the universe, wonders of the natural world, and sweet GIFs from NPR's Science Desk.

Americans buy about 30 million live trees every year. Many end up as mulch, but in some communities they help rebuild dunes, create fish habitat and feed zoo animals. Hear the story of arborial resurrection in anapestic tetrameter.

When physicist Flavio Noca first saw penguins zooming around underwater, he was blown away by their speed and maneuverability. Now, his team has built a robotic arm that perfectly mimics the flippers in action — and he says the device could someday propel underwater craft.

On Dec. 21, 100 years ago, a paper in New York published the first crossword. It quickly became known as a game for the intelligent — even helping Britain recruit code-breakers during WWII. But there isn't much evidence that this brainy game can help stave off dementia.

This year's shower might serve up more than a hundred shooting stars every hour, but the bright streaks could be washed out by a nearly full moon.