 Skip Navigation  14.14: Neptune  Difficulty Level: At Grade
Created by: CK-12 Atoms Practice Practice Neptune Practice Now
How do you think Neptune got its name?  Because of its blue
color, Neptune was named for the Roman god of the sea. This
statue of Neptune is at the Trevi Fountain in Rome.   Neptune,
shown in Figure below, is the only major planet that can’t be
seen from Earth without a telescope. Scientists predicted the
existence of Neptune before it was discovered because Uranus did
not always appear exactly where it should appear. They knew that
the gravitational pull of another planet beyond Uranus must be
affecting Uranus’ orbit.  Neptune was discovered in 1846, in the
position that had been predicted, and it was named Neptune for
the Roman god of the sea because of its bluish color.  Picture
of Neptune  This image of Neptune was taken by Voyager 2 in
1989. The Great Dark Spot seen on the left center in the picture
has since disappeared, but a similar dark spot has appeared on
another part of the