Atget crater on Mercury, MESSENGER image. North is at top. This crater, 100 kilometres across, is located in the Caloris Basin on Mercury, the planet closest to the Sun. This crater is in the northern hemisphere's Liguria quadrangle. It has an interior and ejecta that are darker and bluer than the typical brown volcanic plains. The contrast aids estimates made of the thickness of the volcanic plains. The MESSENGER (Mercury Surface, Space Environment, Geochemistry and Ranging) spacecraft entered orbit around Mercury in March 2011. Image obtained on 9 December 2012, by the Wide Angle Camera (WAC) of the Mercury Dual Imaging System (MDIS).