List of moons

This list of moons restricts itself to the natural satellites of planets and dwarf planets that have secured orbits. For additional moons, see asteroid moons and Trans-Neptunian moons. Satellites massive enough for their gravity to have rounded them into an ellipsoidal shape have their names in bold.

The earliest discovery of a moon other than our own was by Galileo Galilei, who discovered the four Galilean moons in 1610. Over the following three centuries only a few more moons were discovered. Missions to other planets in the 1970s, most notably the Voyager 1 and 2 missions, saw a surge in the number of moons detected. In recent years many more new moons have been discovered, mostly by large ground-based optical telescopes. See Timeline of discovery of Solar System planets and their moons for more information. The list below contains all moons discovered prior to 2008.

Various asteroids are binary asteroids or have satellites orbiting them. These are not listed here; see List of asteroid moons.

Mercury

Mercury, the innermost planet, has no moons larger than 1.6 km.cite journal | url=http://adsabs.harvard.edu/abs/2007P&SS...55.2037W | title=A search for natural satellites of Mercury | last=Warell | first=J. | coauthors=Karlsson, O. | year=2007 | journal=Planetary and Space Science | volume=55 | issue=14 | pages=2037–2041 | doi=10.1016/j.pss.2007.06.004] Note that for a brief time in 1974, Mercury was thought to have a moon; see Mercury's moon.

Venus

Venus has no moons.cite web | url=http://solarsystem.nasa.gov/planets/profile.cfm?Object=Venus&Display=Moons | title=Solar System Exploration: Planets: Venus: Moons | publisher=NASA | accessdate=2008-03-16]

Earth

Earth has one natural satellite, the Moon. It also has at least two co-orbital satellites: the asteroids 3753 Cruithne and 2002 AA₂₉ [cite news
first=David
last=Whitehouse
title=Earth's little brother found
publisher=BBC News
date=21 October 2002
url=http://news.bbc.co.uk/1/hi/sci/tech/2347663.stm
accessdate=2007-03-31 ] ; however these do not count as moons as they do not orbit Earth.

Saturn

Saturn has some 200 known moons and moonlets, 60 with secured orbits.

Pluto

Pluto has three known moons.

Other TNOs

As of September 2008, 58 Trans-Neptunian moons had been discovered.

References