The density of Saturn is so low that if you were to put it in a giant glass of water it would float.
219
If two pieces of metal touch in space, they become permanently stuck together.
808
Sound doesn't travel in space.
255
Astronomer Percival Lowell believed that he was the first person to observe canals on Venus, but because of a faulty adjustment of the eyepiece on his telescope, he was in fact looking at the blood vessels in his own eye.
4
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
Jupiter has radio storms so strong that they can be picked up and heard by an AM radio.
16
The population of the Earth has more than doubled since 1950.
151