Science and Space Facts, Science and Space, Human Body, Health, Earth, Human Disease

Erosion and Weathering
Together with wind, water, and ice, these powerful processes turn rock to sand, sculpt sandstone arches, dissolve limestone, and carve out mountain paths. What else can they do?
Stress Quiz
How much do you know about stress and how it affects your body? Take the quiz and find out—but don't stress about it.
Photo Gallery: Mars
Mars's desolate and rocky landscape has inspired science-fiction writers for years, but what does the red planet really look like? Explore the planet in these firsthand photos.
Mass Extinctions
More than 90 percent of all organisms that have ever lived on Earth are extinct. Learn how millions of creatures can disappear in a geological blink of an eye—and see what might be next.

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NatGeo NewsWatch
Keep current on developments in science, nature, and cultures.
Breaking Orbit: Solve a Space Mystery ... From Your Hot Tub?
Join a discussion of all things extraterrestrial.
BlogWild
National Geographic explorers share tales (and photos) of their adventures.
Stones, Bones 'n Things
Go behind the scenes of new discoveries with National Geographic scientists.
Ocean Now
Join underwater explorer Enric Sala as he explores untouched reefs.

Ultimate Photo Contest
12,000 entries and 28,000 votes—find out who won the grand prize!
Enter Sweepstakes
See photos of Montana and enter for a chance to win a trip for two!