Moons of Our Solar System

Kids drawing of Jupiter and three moons.
Big planets like Jupiter have many moons.

Planetary Pals

Did you know that the Earth is not the only planet or object in space with a moon? There are many moons in our solar sytem.

All but two of the eight planets have moons (Mercury and Venus do not have any moons). Mars has 2 moons, Jupiter has 50, Saturn has 53, Uranus has 27 and Neptune has 13, with Earth's own Moon that makes a grand total of 146 for the moons of the planets. That is a lot! But there are even more. Several asteroids have moons as do many of the dwarf planets. And several additional moons of Jupiter and Saturn just need to be confirmed before they are considered moons. Imagine sitting on Jupiter while watching the night sky and viewing some of its 50 plus moons. That would be quite a sight!

If you have ever looked up at the Moon in the night sky, which I am sure you have, you have noticed that the Moon looks bumpy and spotted. This is because the Moon has many craters on its surface. Actually, all the moons of our solar system are heavily cratered places due to the fact that moons are not big enough to have a sufficient amount of atmosphere to protect themselves from meteors crashing and making craters on their surface.

Moons in our solar system come in all shapes and sizes. Many are round, or ball-like, but many more are not. A lot of the moons look like big, not quite round rocks. Some look like a potato (for example Neptune's moon Naiad), some look like flying saucers (for example Saturn's moons Pan and Atlas) and Saturn's moon Hyperion looks like a sponge.

Some moons are as big or bigger then our own Moon and some are much smaller. The smallest moon of a planet in our solar system is not that small, especially when we compare it to a something big -- big like a football field. An unnamed moon of Jupiter called S/2003 J12 is only 1 km (about 3,281 feet) across, but 1 km is just about equal to the length of 11 football fields placed end zone to end zone! Jupiter's moon Ganymede is the largest moon of our solar system at 5,262 km (about 17,263,780 feet) across. Ganymede is larger than the planet Mercury, larger than the dwarf planet Pluto and three-quarters the size of Mars. In football fields, it would take about 57,550 of them to extend across Ganymede.

Moons continue to be discovered, especially since spacecraft are going farther and to places never visited before. Also, with improved telescopes the moon count continues to grow. You just might discover a moon of one of the planets, dwarf planets or even a moon of an asteroid yourself. There is so much space to explore!

  • We need more drawings of the moons in our solar system. Send us yours.
  • Try putting together this puzzle showing Jupiter and some of its moons. Try more puzzles here.