Martian Limb and Phobos (Natural Colors; credits: NASA/MGS/MSSS)

Una spettacolare veduta del bordo ("limb") di Marte e della sua luna "misteriosa", Phobos, la quale costituisce anche uno degli oggetti più "bui" dell'intero Sistema Solare. Ecco il commento originale a questa immagine:
"Phobos is one of the darkest objects in the Solar System. Thus, 4 wide angle images were obtained to make the picture of Phobos over the martian limb: a pair of red and blue wide angle images was acquired for the limb and a pair of separate images were required to see Phobos. The wide angle images illustrate the fact that Phobos is mostly colorless (dark gray); the faint orange/red hue in the wide angle picture is a combination of slight differences in the focal lengths of the blue and red cameras and the orange/red illumination provided by reflection of sunlight off Mars. To a person standing on Phobos, the Red Planet would fill most of the sky".