Månar och mindre himlakroppar

As we look up at night we see that our Earth has one moon orbiting it, the one we call the Moon. We have explored our moon with orbiters, rovers and astronauts, mapping it and studying its history.Other planets also have moons in orbit around them and these may look quite different from the Earth's moon. Some are small and look like asteroids, others are so icy they would become comets if they plunged on an eliptical orbit towards the inner solar system. One of Jupiter's moon, Ganymede, is so big that its diameter is larger than that of the innermost planet, Mercury.