In this task you will be given an answer to a question. You need to generate a question. The answer given should be a correct answer for the generated question.

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, and a complex geological history revealed in intricate cryovolcanic and tectonic terrains. 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.
what do the moons titan & triton have in common