By: Cara Moore

A. Is the planet terrestrial or jovian?

The larger outer planets such as Saturn, Uranus, Jupiter, and Neptune are jovian planets.

B. What is the length of a year?

The length of year in the planet Neptune is 165 years.

C. What is the length of day?

The day length of Neptune is 16 hours and 6 minutes.

D. How many moons does the planet have?

The planet Neptune has a total of 13 moons in all. Their names are:

  • Triton
  • Nereid
  • Proteus
  • Thalassa
  • Larissa
  • Psamathe
  • Galatea
  • Despina
  • Halimede
  • Naiad
  • Neso
  • Laomeida
  • Sao

E. Does the planet have rings? If yes, what are the rings made of?

Yes, Neptune has several rings. They are thin and dark. The rings are made up of ricks and dust.

F. What is the composition of the atmosphere?

Neptune's atmosphere contains many gases such as, 80% Hydrogen, 19% Helium, and 1,5% Methane.

G. What is the average temperature range?

Neptune's temperature lower to 55 kelvin which is -218 degrees Celsius.

H. What are at least 3 distinguishing characteristics of the planet?

  • Neptune's core is most likely made up of liquid rock.
  • Neptune has the strongest winds in the Solar System.
  • Neptune was discovered by Urbain Le Verrier, John Couch Adams, and Johann Galle on September 23,1846.

I. Name at least 2 missions that have explored the planet and the date they launched.

Voyager 2 in 1989

J. What mythology behind the name of the planet?

Neptune is the god of the sea in Roman mythology and the god Poseidon in Greek mythology.