Summer on Uranus lasts for 21 years.
358
A comet's tail always points away from the sun.
2
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 NASA sent birds into space they would soon die; they need gravity to swallow.
146
One pinhead of the sun's energy is enough to kill a person at a distance of 160 kilometers.
277
The last time that the Sun was in its current position in space around the Milky Way, dinosaurs ruled the Earth.
10
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
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