The 13 moons of Neptune are Despina, Galatea, Halimede, Larissa, Laomedeia, Naiad, Nereid, Neso, Proteus, Psamathe, Sao, Thalassa and Triton. All of these names come from Greek mythology, belonging to characters related to the sea. This naming convention was adopted because Neptune itself was named after the Roman sea god.
In 1846, amateur astronomer William Lassell discovered Triton, Neptune's largest moon. Over the next 157 years, astronomers were able to identify the remaining 12 moons by studying pictures sent by the NASA spacecraft Voyager 2, as well as utilizing advancements made in telescope technology. The final moons of Neptune discovered were identified between 2002 and 2003.