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
The Dallas/Ft. Worth airport is larger than New York City's Manhattan Island.
62
Forest fires move faster uphill than downhill.
52
Australia's Great Barrier Reef is 1,250 miles long!
45
If Manhattan had the same population density as Alaska, there would only be 15 people living there.
138
A volcano has enough power to shoot ash as high as 50 km into the atmosphere.
59