All of the Earth's continents are wider at the north than in the south - and nobody knows why.
194
Pluto is smaller than Russia.
9
If you were to cry in space, the tears would form a bubble in your eye until it's so big it moves to another spot on your face.
10
An organisation called Mars One is planning to establish a permanent colony of humans on Mars by 2023.
9
Sound doesn't travel in space.
255
The heart of an astronaut actually gets smaller when in outer space.
216
The Earth weighs around 6,600,000,000,000,000,000,000 tons (5,940 billion billion metric tons)!
221