Neptune Facts for Kids

Neptune is now the most distant planet (sorry, Pluto) and is a cold and dark world nearly 3 billion miles from the Sun.

In Roman mythology Neptune was the god of the Sea. He is known as Poseidon in Greek mythology. The planet was probably named after the sea gods because of its deep blue color.

This is the symbol for Neptune: 

Neptune is the eighth planet from the Sun and the fourth largest (by size) of the nine planets. Neptune is smaller in size but it’s heavier than Uranus.

Neptune’s blue color is the result of a gas called “methane” in its atmosphere. Like the other gas planets, Neptune has rapid winds trapped in “bands” of latitude and large storms. Neptune’s winds are the fastest in the solar system, reaching 2000 km/hour!

At the time of Voyager’s flyby, Neptune’s most outstanding feature was the “Great Dark Spot” in the southern hemisphere. It was about half the size as Jupiter’s “Great Red Spot” – about 1 Earth would fit into it. Neptune’s winds blew the Great Dark Spot westward at 300 meters/second (700 mph)!

Voyager 2 also saw a smaller dark spot in the southern hemisphere and a small irregular white cloud that zipped around Neptune every 16 hours or so now. This feature is known as “The Scooter.”

Recently, however, the Hubble Space Telescope (HST) showed that the Great Dark Spot has disappeared! Scientists think that it has either dissipated (like our storms do) or is currently being hidden by Neptune’s atmosphere. Also, HST discovered a newdark spot in Neptune’s northern hemisphere. This shows that Neptune’s atmosphere changes rapidly.  

Neptune also has rings. The Voyager 2 spacecraft showed scientists that Neptune indeed has complete rings with bright clumps. Like Uranus and Jupiter, Neptune’s rings are very dark and very faint. Scientists still haven’t figured out what they are made of yet.

Look for Neptune! 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.

Neptune Photos & Movies

  • Neptune
  • A picture of “Scooter”, a bright cloud formation, with spots
  • Bright Neptune clouds
  • Neptune’s “Great Dark Spot”
  • The “Great Dark Spot” and “Scooter”

Image

  • Neptune’s Dark Spot (AVI format)

Neptune Notes

~ Neptune is a giant gas planet which is most likely made up of various “ices” and rock.

~ Neptune has been visited by only one spacecraft, Voyager 2 on Aug 25 1989. Almost everything we know about Neptune comes from this one visit.

~ Depending on how far along Pluto is in its orbit (path around the Sun), Neptune can be either the eighth or ninth planet. Pluto’s orbit is kind of wacky, and it sometimes crosses in front of Neptune. When Pluto does this, Neptune is behind Pluto – hence, it is the ninth planet for a short time.

~ Neptune has 8 known moons; 7 small ones and a large moon called “Triton.”