Psamathe, also known as Neptune X and previously as S/2003 N 1, is an irregular moon of Neptune. It was discovered by Scott Sheppard, David Jewitt, and Jan Kleyna at Mauna Kea Observatory on 29 August 2003. Named after one of the Nereids from Greek mythology, Psamathe follows a distant, highly eccentric, and highly inclined orbit with an average orbital period of about 25 Earth years. Like the majority of irregular moons, Psamathe's orbit is retrograde, meaning it revolves around Neptune in the opposite direction to the planet's orbit around the Sun.
Not who you're looking for? Others named Psamathe: painting by Frederic Leighton · mythical daughter of Crotopus · Nereid of Greek mythology
