Space Station Info :: Neptune

Neptune Moons


Neptune has 14 known moons. Among them, Triton is the largest Neptunian moon, consisting more than 99.5% of the mass. Just 17 days after the discovery of Neptune, William Lassell discovered Triton. Unlike all other large planetary moons in the Solar System, Triton has a retrograde orbit, that denotes that it was captured instead of forming in place. It was once known to be a dwarf planet in the Kuiper belt. Triton was the coldest object, with estimated temperatures of 38 K (-235 C) in 1989.By order of discovery, Neptune's second known satellite, the irregular moon Nereid, has one of the most eccentric orbits of any satellite in the Solar System. The eccentricity of 0.7512 which gives it an apoapsis that is seven times its periapsis distance from Neptune.


Neptune was simply referred to as "the planet exterior to Uranus" or as "Le Verrier's planet". It is the eighth known densest planet from the sun in the solar system. Neptune is massive than its nearest twin Uranus which is 15 times the mass of the earth. It is considered as the densest giant planet as it is the third most heaviest planet. It is the fourth largest planet by diameter and the farthest planet from the Sun . At an average distance of 30.1 AU (4.5 billion km), Neptune orbits sun once in every 164.8 years. Neptune is named after the Roman god of the sea. It has the astronomical symbol ?, a stylised version of the god Neptune's trident.

Physical Characteristics Of Neptune

Neptune's weight is of 1.02431026 kg is intermediate between Earth and the larger gas giants. Neptune's equatorial radius is of 24,764 km which is nearly four times that of Earth. It is 17 times greater than the mass of the Earth but just 1/19th that of Jupiter. Its gravity at 1 bar is 11.15 m/s2, 1.14 times the surface gravity of Earth, and is exceeded only by Jupiter. Neptune is a subclass of giant planet. It is known as ice giant like Uranus. Neptune has been used as a metonym (discovered bodies of similar mass are often referred to as "Neptunes") in the search for extrasolar planets.