We’ve seen spectacular images of Comet Siding Spring from Mars spacecraft, showing just how close the small body was to the Red Planet when it whizzed by Sunday (Oct. 19). But how close were the two objects actually, in the sky? This Hubble Space Telescope composite image shows just how astoundingly near they were. Above … Continue reading "Hubble Composite Picture Shows How Close Siding Spring Comet Was To Mars"