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Planet

Neptune

The farthest planet, an ice giant with the fastest winds measured in the solar system.

NASA/JPL

A planet found with a pencil before it was seen through a telescope, and home to the fastest winds known on any planet.

Neptune, a deep blue globe with a dark storm.
Neptune and its Great Dark Spot, photographed by Voyager 2 in 1989. Credit: NASA/JPL

Neptune is similar in size and composition to Uranus but slightly denser and more massive. Winds in its atmosphere reach about 2,000 km/h.

It was the first planet found by mathematical prediction: irregularities in Uranus’s motion led Urbain Le Verrier to calculate its position, and Johann Galle found it in 1846. Its largest moon, Triton, orbits backwards and is probably a captured Kuiper belt object.

Moons in the knowledge base

Explore it in the orrery

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