Depending on its orbital position, Neptune is often the eighth, sometimes the ninth planet from the sun. The planet Neptune is the smallest of our gas giants, or the planets in our solar system whose mass is primarily made up of gas. It is, like the other gas giants of Saturn, Jupiter and Uranus, without a well defined surface. Therefore, descriptions such as diameter and volume generally refer to the outermost layer.

Although Galileo first spotted Neptune in 1612, Urbain Le Verrier is credited with the official discovery on September 23rd, 1846. While Galileo believed Neptune to be a star, Verrier proved that it was in fact Neptune the planet. It is named after the Roman god of the Sea.

The composition of hydrogen, helium, and methane gives Neptune its unique blue color. It also has faint rings surrounding the planet. For many years, it was believed these rings were not complete. However, when the Voyager 2 reached the Neptune planet on August 25, 1989, their completion was confirmed. Nine moons have been documented in Neptune’s atmosphere, and 4 more are believed to be present.

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