Neptune is the eighth and farthest known planet from the Sun in our solar system. It was discovered in 1846 based on calculations that something was affecting the orbit of Uranus. Neptune is mostly made of hydrogen, helium and methane gas, and is about four times larger than Earth. It has eight known moons, including its largest moon Triton, and takes over 165 years to complete one orbit around the Sun.

1. Neptune
The Blue Planet

2. In This Slide Show…
– The discovery of Neptune
– What a day on Neptune would be like
– Neptune compared to earth
– Facts about Neptune’s moons

3. A New Planet
 Scientists in the early 1800 discovered that the planet
Uranus was not following the orbit they had planned for it.
They guessed that something was pulling on it even farther
out in space. By 1846 astronomers had calculated it’s route
and a few months later, an observer in Germany saw an
unknown object in the sky. It was the new planet,
Neptune. Since then, the information we have gotten about
Neptune has come from observation and from Voyager 2
as it flew by.

4. Neptune

5. Composition
 You could put 60 Earths into Neptune and still
have some room.
 Neptune is mostly made of Hydrogen, Helium and
Methane gas.

6. Interesting Facts
• Neptune actually has not even orbited the sun once
since we discovered it in 1846! It takes 165 years
for it to orbit the sun.
• Triton is moving in the opposite direction that
Neptune is moving and is steadily moving closer
to Neptune. When it collides with Neptune it will
create a ring system that will rival and may exceed
Saturn’s.
• Neptune’s Temperature is about –235 degrees F.
• The Great Dark Spot at Neptune’s equator is not
there anymore, but in 1997, Hubble Space
Telescope saw another similar storm in Neptune’s

7. Statistics
 Neptune has an average distance from the sun of
about 4,497,000,000 kilometers.
 Neptune is about 49,500 kilometers across.
 Neptune rotates once in about 14 hours.

8. Neptune’s Moons
– Neptune has 8 known
moons.
– The largest moon, Triton, is
the coldest known place in
the solar system, with an
average temperature of
–235 degrees Celsius.
– The other moons are Naiad,
Thalassa, Despina, Galatea,
Larissa, Proteus and Nereid.

9. THE END
Special Thanks To NASA for the
information and Pictures!

10. Copyright Information
 Images for this presentation were acquired
at:
 http://solarsystem.jpl.nasa.gov/features/planets/ne