There are 174 known moons out there, spinning around the celestial bodies of our Solar System, so we’ve decided to pick out our favourites. Here, we present our entire ranking of confirmed moons in the solar system. Moons are also very geologically diverse in ways that are truly unimaginable. Some of the greatest prospects for harboring life are in fact moons. Keep up. Subscribe to our daily newsletter. Closest to home and our hearts, the moon is one of the biggest in the solar system, with a radius of 1,737 km. The most interesting things in the Solar System don't have to be planets. Here you can learn about the 30 largest moons (by diameter) in the solar system! If you only count the moons of the planets, there are 166 known moons in the Solar System. Neptune’s moon Proteus is on the edge.) Here is the breakdown: That knowledge is important, too. We’ve learned far less about those planets’ moons. Biggest To Smallest. If you want to see the top 26, click right here.. They are shown here to scale with each other. In the Solar System's habitable zone, there are only three natural satellites—the Moon, and Mars's moons Phobos and Deimos (although some estimates show Mars and its moons to be slightly outside the habitable zone) —none of which sustain an atmosphere or water in liquid form. The Solar System's Major Moons The Solar System contains 18 or 19 natural satellites of planets that are large enough for self-gravity to make them round. The moons, several minor planets and comets of the Solar System, shown to scale. There are over 180 moons that orbit the planets and dwarf planets. Credit: Antonio Ciccolella. Even some of the moons in our solar system are dynamic and interesting worlds and not just boring rocks obscuring our view of a much cooler planet. We learn the planets of the solar system as children, and many school kids could probably name the planets in order of magnitude. (Why the uncertain number? However, over 200 minor-planet moons have also been observed in the Solar System … Knowledge of the moons is greater than ever, thanks to long-range probes and vastly powerful telescopes.