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Triton

Triton, a picture taken by Voyager 2 in 1989 At 2700 kilometres (about 1700 miles) in diameter, Triton is Neptune’s largest moon, and the seventh largest of all the moons in the Solar System. It orbits its parent planet in a reverse direction, the only large moon to do so (the others that do are tiny, irregular objects). Beneath its icy crust lies a mantle of water, which may be liquid if underground temperatures are high enough. On the surface, however, it is extremely cold. With an average surface temperature of -238°C (-396°F), Triton is the coldest world in the Solar System.


A close-up view of the surface of Triton showing its icy surface and geysers bursting out from underneath. The surface is scarred...Read More >>A close-up view of the surface of Triton showing its icy surface and geysers bursting out from underneath. The surface is scarred by valleys and ridges. The rugged cantaloupe terrain of Triton, as viewed from Voyager 2. This scene is of an area about 500 km (300 miles) across....Read More >>The rugged cantaloupe terrain of Triton, as viewed from Voyager 2. This scene is of an area about 500 km (300 miles) across. Vertical relief has been exaggerated by about 25 times, bringing out the ridges and valleys more clearly.

Cantaloupe terrain

Scientists gained knowledge of the surface of Triton when the Voyager 2 space probe flew past Triton in 1989 at a distance of 40,000 kilometres (25,000 miles), sending back detailed images.

Triton comprises more than 99.5% of the total mass of objects that orbit around Neptune.

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