The Solar System is known to contain 176 natural satellites, or moons, excluding those in orbit around small Solar System bodies. 19 moons in the Solar System are large enough to have achieved hydrostatic equilibrium, and thus would be considered planets or dwarf planets if they were in direct orbit around the Sun.

Moons are classed in two separate categories according to their orbits: regular moons, which have prograde orbits (they orbit in the direction of their planets' rotation) and lie close to the plane of their equators, and irregular moons, whose orbits can be pro- or retrograde (against the direction of their planets' rotation) and often lie at extreme angles to their planets' equators. Irregular moons are probably minor planets that have been captured from surrounding space. Most irregular moons are less than 10 kilometres (6.2 mi) in diameter.

The earliest published discovery of a moon other than the Earth's 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, and observations since the year 2000 using mostly large ground-based optical telescopes, have discovered many more, all of which are irregular.

List or lists may refer to:

The List may refer to:

A natural satellite or moon is a celestial body that orbits a planet or smaller body, which is called its primary.

Formally classified moons include 173 planetary satellites orbiting six of the eight planets, and seven orbiting three of the five IAU-listed dwarf planets. As of January 2012^[update], over 200 minor planet moons have been discovered. There are 76 in the asteroid belt (5 with two satellites), 4 Jupiter trojans, 37 near-Earth objects and 9 Mars-crossers. There are also 76 known moons of trans-Neptunian objects. Some 150 additional small bodies were observed within rings of Saturn, but they were not tracked long enough to establish orbits. Planets around other stars are likely to have natural satellites as well, although none have yet been observed.

Of the inner planets, Mercury and Venus have no moons; Earth has one large moon, known as the Moon; and Mars has two tiny moons, Phobos and Deimos. The large gas giants have extensive systems of moons, including half a dozen comparable in size to Earth's moon: the four Galilean moons, Saturn's Titan, and Neptune's Triton. Saturn has an additional six mid-sized moons massive enough to have achieved hydrostatic equilibrium, and Uranus has five. It has been suggested that some satellites may potentially harbour life, though there is currently no direct evidence of life.

Two Moons (1847–1917), or Ishaynishus, was the son of Carries the Otter, an Arikara captive who married into the Cheyenne tribe. Perhaps known best for his participation in battles such as the Battle of the Rosebud against General Crook on June 17, 1876, in the Montana Territory, the Battle of Little Big Horn on June 26, 1876 and what would prove to be his last battle which was that of the Battle of Wolf Mountain on January 8, 1877. Two Moons defeat in the battle at Wolf mountain by General Nelson A. Miles would inevitably lead to the surrender of his Cheyenne band at Fort Keogh in April, 1877.

After the surrender of Two Moons Cheyenne band in 1877, Two Moons would choose to enlist as an Indian Scout for the same General Nelson A. Miles that he had not long since surrendered to. As a result of Two Moons pleasant personality, the friendliness that he showed towards the whites as well as his ability to get along with the military, Two Moons was thus appointed head Chief of the Cheyenne Northern reservation by General Nelson A. Miles. Under the title as head chief, Two Moons would prove to play a crucial role in the assistance of the surrender of Chief Little Cow's Cheyenne band to Fort Keogh.

William Alan Shatner (born March 22, 1931) is a Canadian actor, musician, recording artist, author and film director. He gained worldwide fame and became a cultural icon for his portrayal of James T. Kirk, captain of the USS Enterprise, in the science fiction television series Star Trek from 1966 to 1969, Star Trek: The Animated Series from 1973 to 1974, and in seven of the subsequent Star Trek feature films from 1979 to 1994. He has written a series of books chronicling his experiences playing Captain Kirk and being a part of Star Trek, and has co-written several novels set in the Star Trek universe. He has also authored a series of science fiction novels called TekWar that were adapted for television.

Shatner also played the eponymous veteran police sergeant in T. J. Hooker from 1982 to 1986. Afterwards, he hosted the reality-based television series, Rescue 911 from 1989 to 1996, which won a People's Choice Award for Favorite New TV Dramatic Series. He has since worked as a musician, author, producer, director and celebrity pitchman. From 2004 to 2008 he starred as attorney Denny Crane in the television dramas The Practice and its spin-off Boston Legal for which he won two Emmy Awards and a Golden Globe Award.