The Sahara desert expands at about 1km per month.
90
There's a lake under Antarctica that is 25 million years old called Lake Vostok.
109
Every year, Alaska has about 5,000 earthquakes.
31
The water of the Antarctica is so cold that nothing can rot there.
334
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
Forest fires move faster uphill than downhill.
52
In 1850, only 8% of the people in California were women.
0
10 of the tributaries flowing into the Amazon river are as big as the Mississippi river.
41