(Music) JOAN CARTAN-HANSEN, HOST: The ocean is divided into five different zones based on depth.
The Sunlight Zone goes down about 200 meters or 65 feet.
It is warm and sunny with lots of plants and sea life.
Next is the Twilight Zone.
It goes down from 200 to a thousand meters.
Only a small amount of sun light can get this deep.
The creatures here have large eyes to see in the gloom.
This zone is home to more fish than the rest of the ocean.
Between one thousand meters and four thousand meters in depth is the Midnight Zone.
There's no sunlight here, so the animals may have their own glow.
From four thousand to six thousand feet deep is the Abyssal Zone.
Here, it's pitch black, and the water is nearly freezing.
And finally, from six thousand meters to the bottom of the ocean is the Trench Zone.
We know very little about what lives down there because it's so difficult to explore.
In fact, only about ten percent of the entire ocean's surface has been surveyed.
More people have been to the moon than have been to the deepest part of the ocean.
For more information about oceans, check out the Science Trek website.
You'll find it at ScienceTrek.org