The last time that the Sun was in its current position in space around the Milky Way, dinosaurs ruled the Earth.
10
Mars had an oxygen-rich atmosphere around 4 billion years ago
13
Astronauts get taller when they are in space.
224
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
Tidal forces between the Earth and Moon are slowing the Earth down and pushing the Moon further away.
46
All of the Earth's continents are wider at the north than in the south - and nobody knows why.
194
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
Saturn's rings are about 500,000 miles in circumference but only about a foot thick.
160