Today in the history of astronomy, an eccentric moon of Neptune is found. Voyager 2 obtained this image of Nereid in August 1989. Though taken from 2.9 million miles (4.7 million km) away, it was still enough to reveal details about the moon. Credit: NASA/JPL On May 1, 1949, astronomer Gerard Kuiper spotted a new moon of Neptune while examining photographic plates from McDonald Observatory’s 82-inch telescope. It would be the last moon discovered at that planet until Voyager 2 flew by in 1989. Kuiper proposed calling it Nereid , after the water nymphs who attended Neptune in mythology. Kuiper had discovered a body on one of the solar system’s most eccentric orbits: Nereid’s orbit takes it so far from its planet that it takes 360 Earth days to encircle it. Depending on its location in that orbit, Nereid can range from about 850,000 to about 6 million miles (1.37 million to 9.6 million kilometers) from Neptune. The third-largest of Neptune’s moons, Nereid is also the largest irregular moon in the solar system.…