Pluto, considered the ninth planet in our solar system until it was reclassified to dwarf planet status in 2006, is thought to have undergone an impact that broke off the largest of its five moons, Charon. Because Charon is just over half the size of Pluto, the two bodies then began orbiting each other in a cosmic dance in the Kuiper Belt beyond Neptune’s orbit.
However, a recent study in Nature Geoscience suggests a different origin story for Charon. Using simulations that took into account parameters like the size and composition of the bodies, along with the strength at which they collided, researchers reported that in the early stages of formation Charon and Pluto came together and orbited as one, swapping some materials before separating. They call this cosmic dance a “kiss and capture” event, which could indicate Charon and Pluto are roughly the same age.
