Neptune

Neptune is the eighth planet from the Sun and it is the most distant planet from the Sun. This gas giant planet may have formed much closer to the Sun in early solar system history before migrating (moving) to its present position.

Planet Profile

Mass: 102,410,000,000,000,000 billion kilograms (Neptune weighs as much as 17 and a half planet Earths)

Known Moons: 14

Most Famous Moon: Triton

Known Rings: 5

Orbit Distance: 4,498,396,441 kilometers

Orbit Period/ How Long 1 year is on Neptune: 60,190 Earth days (164.79 Earth years)

Surface Temperature: -201 °C (This is really, really cold! --Much colder than anywhere on Earth ever gets.)

Neptune was discovered on: September 23rd, 1846

Discovered By: Urbain Le Verrier & Johann Galle

Size Of Neptune Compared To The Earth

Facts About Neptune

Unlike Saturn and Venus, Neptune was not known to ancient societities, because it isn't visible to the naked eye.

Neptune is not visible to the naked eye and was first observed in 1846 with a telescope and mathematical predictions. It was named after the Roman god of the sea.

Neptune spins on its axis very rapidly, because it isn't a solid body. It's made of gas and ice.

Neptune's equatorial clouds take 18 hours to make one rotation. In comparison, Earth takes 24 hours to make one rotation.

Neptune makes one trip around the Sun every 164.8 Earth years:

During some parts of its orbit one or the other of its poles point directly at the Sun and get about 42 years of direct sunlight. The rest of the time they are in darkness.

Neptune is the smallest of the ice giants, but not the lightest:

Despite being smaller than Uranus, Neptune has a greater mass. Below its heavy atmosphere, Neptune is made of layers of hydrogen, helium, and methane gases. They enclose a layer of water, ammonia, and methane ice. The inner core of the planet is made of rock.

The atmosphere of Neptune is made of hydrogen and helium, with some methane:

The methane absorbs red light, which makes the planet appear a lovely blue. High, thin clouds drift in the upper atmosphere.

Neptune has a very active climate:

Large storms whirl through its upper atmosphere, and high-speed winds travel around the planet at up 1,340 kilometers per second. One of the largest storms ever seen was recorded in 1989. It was called the Great Dark Spot. It lasted about five years.

Neptune has a very thin collection of rings:

They are likely made up of ice particles mixed with dust grains and possibly coated with a carbon-based substance.

Neptune has 14 moons:

The most interesting moon is Triton, a frozen world that is spewing nitrogen ice and dust particles out from below its surface. It was likely captured by the gravitational pull of Neptune. Neptune's moon, Triton, is probably the coldest place in the solar system.

Only one unmanned spacecraft has flown by Neptune:

In 1989, the Voyager 2 spacecraft swept past the planet. It returned the first close-up images of the Neptune system. The NASA/ESA Hubble Space Telescope has also studied this planet, as have a number of ground-based telescopes.

Inside Neptune (Check out the Layers)

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