The Sahara desert expands at about 1km per month.
90
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 Atlantic Ocean is saltier than the Pacific Ocean.
54
The water between India and Sri Lanka is only 3-30 feet deep and was purportedly passable on foot until 1480 AD when a cyclone moved some sand around.
1
The Amazon rainforest produces more than 20% the world's oxygen supply.
182
The North Atlantic gets 2.5 centimetres (1in) wider every year.
119