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
Sea otters hold hands while sleeping so they don’t drift away from each other.
104
The North Atlantic gets 2.5 centimetres (1in) wider every year.
119
Sharks, like other fish, have their reproductive organs in their chests.
248
The Titanic is about as long as the Empire State building is tall.
174
There are approximately three million shipwrecks on the ocean floor, worth billions in value and treasure.
22
Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
46