Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
46
The light hitting the earth right now is 30 thousand years old.
163
The population of the Earth has more than doubled since 1950.
151
Sound doesn't travel in space.
255
Some asteroids have other asteroids orbiting them.
131
If two pieces of metal touch in space, they become permanently stuck together.
808
The Space Shuttle main engine weighs 1/7th as much as a train engine but delivers as much horsepower as 39 locomotives.
147