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Neptune, moons





Neptune has 13 known moons. All of the small, irregular moons that lie beyond Nereid have been discovered since 2002. In addition a candidate moon has been identified and named c02N4. This was discovered on Aug. 14, 2002, and seen again using the Very Large Telescope (VLT) on Sep. 3, 2002. However, further attempts to spot this object failed. c02N4 could be a Centaur – an object that has migrated from the Kuiper Belt – but its lack of movement relative to Neptune is more consistent with it being a satellite. See also Neptune Trojan.


moon orbit semi-major
axis (km)
orbital
period (d)
eccentricity orb. incl.
(º)
diameter
(km)
Naiad 48,227 0.294 0.0003 4.75 96 × 60 × 52
Thalassa 50,075 0.311 0.0002 0.21 108 × 100 × 52
Despina 52,526 0.335 0.0002 0.22 180 × 150 × 130
Galatea 61,953 0.429 0.0001 0.05 204 × 184 × 144
Larissa 73,548 0.555 0.0014 0.25 216 × 204 × 164
Proteus 117,647 1.122 0.0005 0.52 436 × 416 × 402
Triton 354,800 5.877R 0.0000 157.3 2,707
Nereid 5,513,000 360.14 0.7512 32.55 340
S/2002 N1 15,728,000 1879.7 0.571 134.1 62
S/2002 N2 22,422,000 2914.1 0.293 48.51 44
S/2002 N3 23,571,000 3167.9 0.424 35 42
Psamathe 46,695,000 9115.9 0.450 146.6 24
S/2002 N4 48,387,000 9374.0 0.495 132 60


Related category

   • PLANETS AND MOONS