Phobos imaged by HRSC’s nine imaging channels

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.