Triton, the largest moon of Neptune. Because Triton has a retrograde orbit (opposite that of it's planet), it was likely captured by Neptune's gravitational pull from the Kuiper Belt. It's about the same size and has a very similar makeup to Pluto, another Kuiper Belt object. Triton's orbit is slowly shrinking, and it is expected that in about 3.6 billion years, it will either collide with Neptune or be destroyed, forming a Saturn-like ring system.
Tritón creciente. Es una luna retrógrada (gira en sentido contrario al resto de los satélites de Neptuno), lo que hace pensar que se trata de un "cuerpo capturado" por la gravedad de Neptuno, y que quizá se formo en otro sitio (¿el cinturón Kuiper?).
Moon: Triton Parent Planet: Neptune Why You Should Know it: Of all the biggest, "major" moons in the solar system, Triton is the only one that orbits in a direction opposite that of its parent planet's rotation. Astrophysicists call this a "retrograde orbit," and it's typical of moons that have been "captured" by their parent planet.