Neptune

Neptune is the eighth, and most distant planet from the Sun. It’s the fourth-largest, and the first planet discovered with math.

Neptune Facts

Dark, cold and whipped by supersonic winds, giant Neptune is the eighth and most distant major planet orbiting our Sun.

More than 30 times as far from the Sun as is Earth, Neptune is not visible to the naked eye. Neptune was the first planet located using math.

Get the Facts

Neptune is blue and banded with clouds and storms.

This picture of Neptune was produced from images taken by NASA’s Voyager 2 in the summer of 1989. It was the first spacecraft to fly by the planet.

NASA/JPL-Caltech

Neptune by the Numbers

How big is Neptune? How far is it from the Sun?

Use this tool to compare Neptune to Earth, and other planets.

Blue Neptune and its storms as seen from a spacecraft.

This photograph of Neptune was reconstructed from two images taken by Voyager 2.

NASA/JPL-Caltech

Neptune Exploration

Galileo recorded Neptune as a fixed star during observations with his small telescope in 1612 and 1613.

More than 200 years later, the ice giant became the first planet located through mathematical predictions rather than through observations of the sky. In 1989, NASA's Voyager 2 became the first -and only - spacecraft to study Neptune up close.

A large rocket carrying NASA's Voyager 2 spacecraft is seen through the trees as it lifts off with fire and smoke below it.

NASA's Voyager 2 lifts off on Aug. 20, 1977, from Kennedy Space Center in Florida.

NASA/JPL-Caltech

Neptune Moons

Neptune has 16 known moons.

English merchant and astronomer William Lassell discovered the first and largest of Neptune's moon – Triton – on Oct. 10, 1846, just 17 days after a Berlin observatory discovered Neptune.

Explore Neptune's Moons

Orbit diagram showing several Neptune moons.

This diagram shows the orbits of several of Neptune's moons.

NASA, ESA, and A. Feild (STScI)

Ice Giant Resources

Resources for Neptune and Uranus.

Explore a curated collection of resources about ice giants, including activities that can be done at home, as well as videos and animations, images, and posters.

A light blue-green circle represents the planet Uranus (at left). A dark blue circle with white wispy clouds at the center represents the planet Neptune (at right).

NASA/JPL-Caltech

Eyes on the Solar System lets you explore planets, moons, asteroids, comets, and the spacecraft exploring them from 1950 to 2050.

Learn More

For Kids: All About Neptune
Facts about Neptune for Kids.
Ice Giant Resources
A curated collection of resources, including activities that can be done at home, as well as videos and animations, images, and posters.
NASA Photojournal: Neptune
Images of Neptune from NASA spacecraft.