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  1. Home
  2. Solar System
  3. Neptune
  4. Moons

Moons of Neptune

Neptune has 16 known natural satellites.

About Neptune's Moon System

Neptune has 16 known moons, dominated by the massive Triton, which contains more than 99.5 percent of all mass orbiting the planet. Triton is unique among large moons because it has a retrograde orbit -- it orbits in the opposite direction to Neptune's rotation. This strongly suggests Triton was once a Kuiper Belt object captured by Neptune's gravity. With a diameter of 2,707 km, Triton is the seventh-largest moon in the solar system. Its surface temperature of about -235 degrees Celsius makes it one of the coldest known objects. Despite this extreme cold, Triton is geologically active, with nitrogen geysers observed by Voyager 2 shooting material up to 8 km above the surface. The remaining moons are much smaller and include both regular inner moons and distant irregular satellites.

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Explore Other Moon Systems

Earth (1)Mars (2)Jupiter (95)Saturn (146)Uranus (28)Pluto (5)
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Neptune Overview

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