This past Tuesday, photographer Chris Cook snapped this image of M31 (Messier 31), more commonly known as the Andromeda Galaxy. It shared the sky with the PanSTARRS comet, which is making its way through the solar system.
Cook produced this composite image by conducting four 20-second exposures taken with a Canon 40D at ISO800 and a 70-200mm f/2.8L lens. The camera was tracked during the exposures using an Orion EQ-1 equatorial mount. It was taken on the evening of April 2, 2013, near his home in Harwich, Mass. To see more of Cook’s work, simply click here: Chris Cook Photography