One cubic mile of seawater contains about 50 pounds of gold.
79
10 of the tributaries flowing into the Amazon river are as big as the Mississippi river.
41
Israel's Dead Sea is 1,312 feet below sea level.
48
It takes a drop of ocean water more than 1,000 years to circulate around the world.
61
An earthquake on Dec. 16, 1811 caused parts of the Mississippi River to flow backwards.
243
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
More than 25% of the world's forests are in Siberia.
51