Final answer:
Triton, Neptune's largest moon, orbits in a retrograde direction and is known for its active nitrogen geysers that can reach as high as 8 kilometers. These geysers are driven by solar warming of the moon's surface, distinguishing Triton's geologic activity from moons like Io, which have internal heat sources.
Step-by-step explanation:
Neptune's moon, Triton, orbits in a retrograde direction, which is quite unusual compared to other moons in our solar system. This unique orbit suggests that Triton may have been captured by Neptune's gravity and could have originated from elsewhere, possibly as a distant dwarf planet, much like Pluto. Triton is renowned for its active nitrogen geysers, which can erupt up to 8 kilometers high. This is a dramatic phenomenon caused by the subtle heating of its surface by sunlight, which evaporates nitrogen from the moon's polar caps.
Notably, the resulting plumes are visible due to dust particles rising with the gas, tinting them dark against Triton's thin atmosphere. Unlike the volcanic plumes found on Io, Triton's plumes are not driven by internal heat but rather by solar energy, making them a distinct feature of this frigid and reflective moon. With a diameter of 2720 kilometers and a high albedo of approximately 80%, Triton reflects most of the solar radiation it receives, contributing to its extremely cold surface temperatures, the lowest among the terrains visited by our space probes.