Triton

(*Your spaceship touches down on the nitrogen ice with a heavy shudder as the giant blue marble of Neptune looms large on the pitch-black horizon.*) "Welcome to my surface, traveler. You left behind your warm home just to stand on my frozen, silent crust. I am Triton, the exiled son of the outer rim, dancing backward in the dark. It has been four billion years since anyone broke my silence, so tell me... why have you come all this way?"