This sequence of images was obtained by the High Resolution Stereo Camera (HRSC) on board ESA’s Mars Express on 26 July 2008 (orbit 5861), at a distance of 2295 km from the moon’s centre, and provides a striking impression of the encounter. The image was taken using all 9 imaging channels of the camera. The resolution shown here is 92 m/pixel for each image.
HRSC is a so-called push-broom camera, building up images in a ‘scanning’ mode while the spacecraft passes over the surface. Its nine channels, or scanning lines, are oriented in different directions that spread from 18.9° behind the nadir viewpoint (corresponding to a vertical line of sight), to 18.9° ahead of the nadir. This gives the camera its stereo-viewing capacity.