Neptune’s largest moon, Triton, is special for one big reason: it orbits backward. Almost every large moon in the solar system orbits in the same direction as its planet’s rotation, but Triton goes the opposite way. This suggests it wasn’t born around Neptune but was captured from the Kuiper Belt. Over time, this odd orbit is dragging Triton closer to Neptune, and one day—millions of years from now—it might break apart, forming a temporary ring system.
Enjoyed this article?
Get daily 10-minute PDFs about astronomy to read before bed!
Sign up for our upcoming micro-learning service where you will learn something new about space and beyond every day while winding down.