Phobos from Spirit and Mars Express

Taking advantage of extra solar energy collected during the day, Spirit settled in for an evening of stargazing, photographing Deimos and Phobos. The first 2 images in this sequence show gradual enhancements in the surface detail of Mars' largest moon, Phobos, made possible through a combination technique known as stacking. In stacking scientists use a mathematical process known as Laplacian sharpening to reinforce features that appear consistently in repetitive images and minimize features that show up only intermittently. In this view of Phobos, the large crater named Stickney is just out of sight on the Moon's upper right limb.
Spirit acquired the first 2 images with the PanCam on the night of Sol 585 (Aug. 26, 2005). The far right image of Phobos, for comparison, was taken by the HR Stereo Camera on Mars Express. The third image in this sequence was derived from the far right image by making it blurrier for comparison with the panoramic camera images to the left. More information about the Mars Express image is available at http://www.esa.int/SPECIALS/Mars_Express/SEM21TVJD1E_1.html