The Space Shuttle main engine weighs 1/7th as much as a train engine but delivers as much horsepower as 39 locomotives.
147
In the last 7 years, humanity has discovered 43 potentially habitable planets.
14
41% of the moon is not visible from earth at any time.
103
Some asteroids have other asteroids orbiting them.
131
A 100-pound person on Earth would weigh 38 pounds on Mars.
102
A comet's tail always points away from the sun.
2
Astronauts get taller when they are in space.
224
An organisation called Mars One is planning to establish a permanent colony of humans on Mars by 2023.
9