41% of the moon is not visible from earth at any time.
103
It 'snows' metal on Venus.
13
Saturn's rings are about 500,000 miles in circumference but only about a foot thick.
160
Venus is the only planet that rotates clockwise.
310
The heart of an astronaut actually gets smaller when in outer space.
216
Astronauts get taller when they are in space.
224
One pinhead of the sun's energy is enough to kill a person at a distance of 160 kilometers.
277