When did William Lassell discover Neptune's largest moon?
William Lassell discovered Neptune's largest moon on the 10th of October 1846. This discovery occurred just seventeen days after astronomers first identified the planet itself.
William Lassell discovered Neptune's largest moon on the 10th of October 1846. This discovery occurred just seventeen days after astronomers first identified the planet itself.
International Astronomical Union guidelines now require all Neptunian moons to bear names from Greek water deities or creatures. Names like Proteus and Despina come from children of Poseidon while Larissa represents a lover of Poseidon.
Triton follows a retrograde orbit around Neptune unlike any other large moon. Its path tilts twenty-three degrees relative to Neptune's equator suggesting gravitational capture rather than formation alongside the planet.
The Voyager 2 spacecraft mission in 1989 revealed five additional inner moons including Naiad and Thalassa. Harold J. Reitsema observed Larissa during a stellar occultation on the 24th of May 1981 before that mission.
Nereid dominates this group holding ninety-eight percent of their combined mass if Triton is excluded. The Sao group includes Halimede Sao S/2002 N 5 and Laomedeia following prograde paths.