Charon, to begin bursting at the seams, much like Marvel’s green superhero the Hulk.
A newly released image of Charon from NASA’s New Horizons spacecraft suggests that some of the fractures on that moon’s surface may be the result of a once-liquid ocean beneath the surface freezing over time. That may have resulted in the signs of expansion on Charon’s surface that NASA scientists compared to “Bruce Banner tearing his shirt as he becomes the Incredible Hulk.”
The largest of Pluto’s five moons, Charon is about 750 miles (1,200 kilometers) in diameter, about half as wide as Pluto. Because the center of mass of the Pluto-Charon system lies beyond Pluto’s surface, the two are frequently regarded as a twin planet system.