The Caspian Sea is also classed as the world's largest lake.
52
Two dogs were among the Titanic survivors.
262
Sharks, like other fish, have their reproductive organs in their chests.
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In 1992, 29,000 rubber ducks washed off a ship. They were found thousands of miles away 8 years later.
707
Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
46
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
There are approximately three million shipwrecks on the ocean floor, worth billions in value and treasure.
22
The North Atlantic gets 2.5 centimetres (1in) wider every year.
119