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.

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.

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.

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.

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. 

Dive down, down, and down a whole lot more—until you've traveled 2,400 meters to the sea floor. Can you picture how deep that really is? Compare it with the height of famous landmarks, and you will.

For oceanographers, the work they do at sea is just the beginning. Learn more about the discoveries made by one scientist who completed more than 100 dives to the sea floor.

Submarine hot springs, called hydrothermal vents, spew out mineral-rich hot water. What do scientists hope to learn by tracking the temperature variations around these vents for an entire year?