Taken on April 24, 2019, this rainbow-colored image shows the Martian moon Phobos, as viewed by NASA's 2001 Mars Odyssey orbiter using its infrared camera, Thermal Emission Imaging System (THEMIS). Each color represents a different temperature range, with the warmest in the center and coolest on the outer edge. This was the first time THEMIS was used to observe Phobos while in a full moon phase, which offers scientists a much better view for studying the composition of the Martian moon. Previous half-moon views, which can be seen here, were better for studying surface textures. https://photojournal.jpl.nasa.gov/catalog/PIA23204