41% of the moon is not visible from earth at any time.
103
It would take more than 150 years to drive a car to the sun.
569
Astronomer Percival Lowell believed that he was the first person to observe canals on Venus, but because of a faulty adjustment of the eyepiece on his telescope, he was in fact looking at the blood vessels in his own eye.
4
The Sun and Moon appear to be the same size because the moon is 400 times smaller than the Sun, but 400 times closer to Earth.
13
The heart of an astronaut actually gets smaller when in outer space.
216
An organisation called Mars One is planning to establish a permanent colony of humans on Mars by 2023.
9