One asteroid strike may explain two mysteries of Mars’ moon Deimos

A single asteroid impact may explain two of Deimos’s most puzzling features: its huge southern depression and unusually smooth, dusty surface. Simulations suggest a roughly 320-meter asteroid struck the Martian moon at an angle, throwing debris around the entire world without breaking it apart. New observations from ESA’s Hera spacecraft support the scenario and indicate that Deimos is surprisingly porous and fragile.