30 January 1987
Vol 235, Issue 4788

About The Cover

Enhanced color image of Central Valles Marineris, Mars, where the suspected recent volcanism occurred. The photograph is a composite of high-resolution images in black and white and low-resolution images in color. Some of the dark material covering the Valles Marineris floor in the image is the material that may have come from volcanic vents and was dispersed by the wind. See page 565. [Alfred S. McEwen, U.S. Geological Survey, Flagstaff, AZ 86001]