Space Facts for Kids
Out-of-this-world facts about the universe
The average distance between Earth and the Moon is so large that all seven other planets in the solar system could fit in that gap side by side with room to spare.
Olympus Mons on Mars is so wide that if you stood at its centre, its edges would be below the horizon — meaning you could not see that you were on a volcano at all.
Jupiter, Saturn, Uranus, and Neptune are called gas giants because they are made mainly of hydrogen and helium with no solid surface to stand on. You would simply sink into the planet.
Earth's magnetosphere deflects the lethal stream of charged particles from the Sun called the solar wind, making life on the surface possible. Without it, the solar wind would strip away our atmosphere.
When you look at a star in the night sky, you are seeing the past. The light from even nearby stars left hundreds of years ago. Some stars you can see may no longer exist.
NASA's Space Shuttle was the first spacecraft designed to be mostly reusable. Its solid rocket boosters were recovered from the ocean and refurbished for later flights.
Phobos, Mars's inner moon, orbits so close to Mars that it completes three orbits per Martian day. It is also slowly spiralling inward and will eventually crash into Mars or break apart.
Gravity slows down time — a prediction of Einstein's general relativity. GPS satellites must account for this effect, or navigation errors would build up by about 10 kilometres per day.
Ceres is the largest object in the asteroid belt between Mars and Jupiter, containing about a third of the belt's total mass. It is classified as a dwarf planet, the same category as Pluto.
The Andromeda Galaxy, our nearest large galactic neighbour, is visible to the naked eye on a dark night as a faint smudge — making it the most distant object humans can see without a telescope.