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How long does Neptune take to orbit the Sun?

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Clouds in Neptune's atmosphere — Neptune A photograph of clouds in Neptune's atmosphere, taken by Voyager 2 in August 1989. The view is from below the planet's equator, and north is up. The Great Dark Spot (center left) is 13,000 km (8,100 miles)—about the diameter of Earth—in its longer dimension. Accompanying it are bright, wispy clouds thought to comprise methane ice crystals. At higher southern latitudes lies a smaller, eye-shaped dark spot with a light core (bottom left). Just above that spot is a bright cloud dubbed Scooter. Each of these cloud features was seen to travel eastward but at a different rate, the Great Dark Spot moving the slowest.

Neptune has an orbital period of 164.79 Earth years to complete one revolution around the Sun.12

Because of this long duration, the planet has completed only one orbit since its discovery in 1846. Neptune's orbit is notably circular, with an eccentricity of 0.0086, which is the second lowest among the planets in the solar system.12