Unlike human visitors, Antarctica's plants and animals don't require high-tech gear. How have these organisms adapted to thrive—not just survive—in such an extreme environment?

Even during the summer months, the temperatures on Antarctica's coast range around freezing. Inland, it's even chillier. Discover the three reasons why this continent is the coldest place on Earth.

Climb aboard this virtual expedition, and take charge of the ship's controls. You'll travel a 40-kilometer (24.8-mile) stretch of the Juan de Fuca Ridge, looking for a deep sea vent.

If the Earth turns all the way around every 24 hours, then why are some days longer than others? And why do we have winter and summer? See the answers for yourself—in a matter of seconds.

If the Earth turns all the way around every 24 hours, then why are some days longer than others? And why do we have winter and summer? See the answers for yourself—in a matter of seconds.

You don't need to leave Earth to find life forms that can exist in the harshest of environments. This marine geologist discusses the exciting research being done at the bottom of the ocean.

What does it take to send a crew to the bottom of the ocean? A sub with 14-inch-thick walls made of a titanium-steel alloy—and a day of calm seas to ensure smooth diving.

How pressurized is the ocean floor? Imagine an elephant standing on your big toe—then apply that pressure to your whole body. But thanks to ALVIN, scientists can make the dive comfortably.

What does it take to send a crew to the bottom of the ocean? A sub with 14-inch-thick walls made of a titanium-steel alloy—and a day of calm seas to ensure smooth diving. 

At the ocean's surface, winds create waves and currents. So why, then, are there currents moving all the way down at the deepest depths? Find out what's behind all this deep sea churning.