The typical spec of dust that you see floating in the air is half way in size between the Earth and a subatomic particle.
131
An unprotected human can survive up to 1.5 minutes in space with no permanent bodily damage.
82
A neutron star (what remains after a Super Nova) is so dense that a portion of it the size of a sugar cube would weigh as much as all of humanity, or more than all the cars in the United States.
5
Jupiter is bigger than all the other planets combined.
254
The Space Shuttle main engine weighs 1/7th as much as a train engine but delivers as much horsepower as 39 locomotives.
147
The sun is 330,330 times larger than the earth!
190
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
The heart of an astronaut actually gets smaller when in outer space.
216