Neptune is the eighth planet from the Sun and last of the known planets. While it is the third largest planet with respect to mass, it is only the fourth largest in terms of diameter. Due to its blue coloration, Neptune was named after the Roman god of the Sea.It takes Neptune 164.8 Earth years to orbit the Sun.Neptune was discovered by Jean Joseph Le Verrier.The orbit path of Neptune is approximately 30 astronomical units (AU) from the Sun.The largest Neptunian moon, Triton, was discovered just 17 days after Neptune itself was discovered.Neptune has a storm similar the Great Red Spot on Jupiter.Neptune is the eighth planet from the Sun and the fourth largest (by diameter). Neptune is smaller in diameter but larger in mass than Uranus.Neptune has been visited by only one spacecraft, Voyager 2 on Aug 25 1989. Much of we know about Neptune comes from this single encounter. But fortunately, recent ground-based and HST observations have added a great deal, too.Neptune’s blue color is largely the result of absorption of red light by methane in the atmosphere but there is some additional as-yet-unidentified chromophore which gives the clouds their rich blue tint.Neptune can be seen with binoculars (if you know exactly where to look) but a large telescope is needed to see anything other than a tiny disk.