A comet's tail always points away from the sun.
2
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
46
If two pieces of metal touch in space, they become permanently stuck together.
808
There are more nerve cells in the human brain than there are stars in the Milky Way.
349
On Titan, Saturn's largest moon, the atmosphere is so thick and the gravity so low that humans could fly through it by flapping "wings" attached to their arms.
7
The light hitting the earth right now is 30 thousand years old.
163