Martian Sunrise par Corbin Davenport

This computer-generated image depicts part of Mars at the boundary between darkness and daylight, with an area including Gale Crater, beginning to catch morning light. Image from NASA. "You may use NASA imagery, video, audio, and data files used for the rendition of 3-dimensional models for educational or informational purposes, including photo collections, textbooks, public exhibits, computer graphical simulations and Internet Web pages. This general permission extends to personal Web pages."