Mars had an oxygen-rich atmosphere around 4 billion years ago
13
The Earth gets heavier each day by tons, as meteoric dust settles on it.
118
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
Sound doesn't travel in space.
255
There are 5 to 10 times more stars in the known Universe than there are grains of sand on all the world's beaches, but a single grain of sand has more atoms than there are stars in the known Universe.
20
If you were to cry in space, the tears would form a bubble in your eye until it's so big it moves to another spot on your face.
10
The sun puts out more power in 1 second than mankind has ever used within human existence.
14