One of the most interesting places in the solar system is Triton, moon of Neptune.

It orbits backwards which means it wasn’t formed with Neptune: it was captured.

There have been cases of rogue planets drifting alone through interstellar space - could Triton be one such planet, forced into submission by the gas giant?

Of further interest is the discovery that there may be several sources of internal heat for the moon: radioactive isotopic decay and tidal flexing.

The high amounts of ammonia (which would significantly lower the temperature in which water would exist in liquid form) and the internal heat could mean there’s a subsurface ocean of water…

It could be a unique opportunity to explore a planet from another solar system with our robots or another likely candidate for extraterrestrial life… the only thing we know for sure is that there’s a lot we don’t know.

The only time we’ve visited was when Voyager 2 flew by briefly in 1989.

NASA currently has no further plans to visit Triton…