More than a dozen men have stood on the surface of the moon, but only three have been to Challenger Deep in the Marianas Trench, the deepest known spot in the ocean.
17
It takes a drop of ocean water more than 1,000 years to circulate around the world.
61
Even Antarctica has an area code. It's 672.
58
There are approximately three chickens for every human on Earth.
13
10 of the tributaries flowing into the Amazon river are as big as the Mississippi river.
41
An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
243
The city of Houston, Texas is built on a swamp and is slowly sinking!
89
In 1850, only 8% of the people in California were women.
0