The Sun and Moon appear to be the same size because the moon is 400 times smaller than the Sun, but 400 times closer to Earth.
13
Sound doesn't travel in space.
255
One pinhead of the sun's energy is enough to kill a person at a distance of 160 kilometers.
277
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
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
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
Saturn's moon, Mimas, not only looks like the Death Star, it also has a Pac Man heat signature.
15