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
Neil Armstrong, the first man to step foot on the moon, carried with him a piece of cloth and wood from the original 1903 Wright Flyer.
12
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
Pluto is smaller than Russia.
9
The light hitting the earth right now is 30 thousand years old.
163