Location of Airy 0 crater on Mars

The 0.5-kilometre-wide crater, subsequently named 'Airy-0' (within the larger crater Airy), chosen as the zero degrees longitude point. Here the outlines of the Mariner 9, Viking and Mars Global Surveyor images are shown on a wide-angle context image taken by the US Mars Global Surveyor (MGS) Mars Orbiter Camera (MOC).