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
41% of the moon is not visible from earth at any time.
103
The density of Saturn is so low that if you were to put it in a giant glass of water it would float.
219
Neil Armstrong, the first man to step foot on the moon, carried with him a piece of cloth and wood from the original 1903 Wright Flyer.
12
The population of the Earth has more than doubled since 1950.
151
A comet's tail always points away from the sun.
2
The sun is 330,330 times larger than the earth!
190
In space, astronauts cannot cry properly, because there is no gravity, so the tears can't flow down their faces!
175