This ultraviolet image of Mars was taken on 24 February 2007 with the OSIRIS wide-angle camera through the 'OH' colour filter, intended for the indirect detection of water when observing comet 67/P Churyumov-Gerasimenko.

Clouds are visible at the North polar cap of Mars and at the morning 'limb' (border or outermost edge of a celestial body). A high-altitude cloud is also visible and shown in the inset.