Is your tree robust to cold? Do its needles cling to their branches? Christmas tree scientists ask these questions so we don't have to.
For better or worse
The space rock could hold clues to the origins of our solar system, and maybe even life on Earth.
History's best time, set by Usain Bolt, is 9.58 seconds. Depending on how you parse the data, he's either rather close—or worlds away—from the theoretical limit.
NASA's Mars lander, called InSight, landed on the red planet and sent its first image of the Mars surface.
These livestreams will let you follow along as the InSight spacecraft lowers itself to the surface of Mars.
The latest robot to visit the red planet is built to withstand dust storms and temperatures that can melt steel during entry, descent, and landing.
Here are the best livestreams and watch parties to keep tabs on the spacecraft as it completes its Mars landing Monday.
Smoke from the Camp, Hill, and Woolsey fires has forced Californians to don air masks. But measuring air quality is more complex than you might think.