Extraterrestrial meteors: A martian meteor and its parent comet

Regular meteor showers occur when a planet approaches the orbit of a periodic comet — for example, the Leonid shower is evident around 17 November every year as Earth skims past the dusty trail of comet Tempel–Tuttle. Such showers are expected to occur on Mars as well, and on 7 March last year, the panoramic camera of Spirit, the Mars Exploration Rover, revealed a curious streak across the martian sky. Here we show that the timing and orientation of this streak, and the shape of its light curve, are consistent with the existence of a regular meteor shower associated with the comet Wiseman–Skiff, which could be characterized as martian Cepheids.