astronomylabMeet the Moon
Ice giant / World 08

Neptune

At the edge of the planetary realm.

Neptune is a cold, windy ice giant far beyond the warmth of the inner solar system. It was found after calculations predicted where an unseen planet should be.

Explore this orbit ↗
Neptune, NASA and mission partners

Image: NASA / JPL-Caltech; Voyager 2 (processed color). Processed mission imagery; apparent color varies with filters and processing.

Equatorial diameter49,528 km
One orbit163.72 years
Distance from Sun30.18 AU
Solar day16.1 hours

Neptune compared with Earth

Its equatorial diameter is 3.88 times Earth’s. Its mass is 17.09 times Earth’s, while its orbital period is 163.75 Earth years.

The reference gravity is about 11 m/s². These rounded values include the reference conventions used in NASA’s fact sheet; the ideal spherical gravity calculator can differ slightly.

NASA reference data ↗

Keep wondering

A few good questions

How far is Neptune from the Sun?

Neptune has a mean orbital distance of about 4,515 million kilometers, or 30.18 AU. Its actual distance varies through its elliptical orbit.

How long is a year on Neptune?

An orbit takes approximately 59,800 Earth days. The orbit simulator lets you see how distance affects the length of a year.