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
An international team of astronomers has spotted the farthest known gravitational lens and, as Albert Einstein predicted, it is a galaxy that deflects and intensifies the light of a much further object.
9
The earth rotates more slowly on its axis in March than in September.
145
The population of the Earth has more than doubled since 1950.
151
The Space Shuttle main engine weighs 1/7th as much as a train engine but delivers as much horsepower as 39 locomotives.
147
Venus is the only planet that rotates clockwise.
310
Earth is the only planet in our solar system that's not named after a god or goddess.
17
