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How do geyserlike plumes form on Triton?

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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.

Geyserlike plumes on Triton are formed when nitrogen gas escapes through vents in the moon's icy surface, carrying entrained dust particles to heights of approximately 8 km (5 miles).1

While the precise mechanisms and energy sources driving these plumes are not yet fully understood, their tendency to occur at latitudes illuminated vertically by the Sun indicates that incident sunlight plays a significant role in the process. Once the plumes reach their peak altitude, the dust is transported downwind for distances as far as 150 km (90 miles). These active features were first observed during the Voyager 2 flyby in 1989, which provided the primary data regarding the moon's surface activity.12