Bruce Murray Space Image LibraryPluto's dark side Pluto's dark side New Horizons took this stunning image of Pluto only a few minutes after closest approach on July 14, 2015. The image was obtained at a high phase angle -- that is, with the sun on the other side of Pluto, as viewed by New Horizons. Seen here, sunlight filters through and illuminates Pluto's complex atmospheric haze layers. The southern portions of the nitrogen ice plains informally named Sputnik Planum, as well as mountains of the informally named Norgay Montes, can also be seen across Pluto's crescent at the top of the image. Looking back at Pluto with images like this gives New Horizons scientists information about Pluto's hazes and surface properties that they can't get from images taken on approach. The image was obtained by Ralph MVIC approximately 21,550 kilometers from Pluto, about 19 minutes after New Horizons' closest approach. The image has a resolution of 430 meters per pixel. Pluto's diameter is 2,374 kilometers.