Mars had an oxygen-rich atmosphere around 4 billion years ago
13
If two pieces of metal touch in space, they become permanently stuck together.
808
The heart of an astronaut actually gets smaller when in outer space.
216
The sun is 330,330 times larger than the earth!
190
A comet's tail always points away from the sun.
2
Only 55% of Americans know that the sun is a star.
986
Earth is the only planet in our solar system that's not named after a god or goddess.
17
Lightning strikes about 6,000 times per minute on this planet!
158