Hippocamp, the smallest moon of Neptune, is named for a sea monster in Greek mythology. The hippocamp, sometimes known as the hippocampus, is said to have a horse body and a fish tail, depicted in Greek and Roman artwork.
The journal said that the moon is only 21 miles in diameter, USA Today reported. In comparison, Neptune is about 30,599 miles in diameter, and Earth’s moon is 2,159 miles in diameter, while the Earth is 7,917.5 miles in diameter. more