With its signature crater, the largest of Mars’ two moons, Phobos, is sometimes called the Death Star, calling to mind the “technological terror” prominent in the Star Wars films. The moon has not only spurred the public’s imagination, but that of astrophysicists as well. Many had wondered how the impact that created such a huge crater could have done so without destroying the entire body. At nine kilometers in diameter, the crater, Stickney, takes up a huge amount of the moon’s surface—for scale, the entire moon is only 70 kilometers around.
