A new 3D map of galaxy clusters has just been published by a research team led by Maguerite Pierre from the Astrophysics Department-AIM Laboratory of CEA-IRFU through a survey of two regions of the sky, each covering about 25 square degrees (about 100 times the area of the full moon). The survey, called XXL, was conducted from 2011 to 2013 resulting from 543 observations of the X-ray satellite XMM-Newton and requiring over 6 million seconds exposure.