Triton is one of the few moons in the Solar System known to be geologically active (the others being Jupiter 's Io and Europa, and Saturn 's Enceladus and Titan). As a consequence, its surface is relatively young, with few obvious impact craters. Intricate cryovolcanic and tectonic terrains suggest a complex geological history. Part of its surface has geysers erupting sublimated nitrogen gas, contributing to a tenuous nitrogen atmosphere less than 1 / 70,000 the pressure of Earth 's atmosphere at sea level. It is the second - largest planetary moon in relation to its primary, after Earth 's moon.
how are saturn's moon titan and neptune's triton similar
geologically active