sci17032a

Finding a dwarf galaxy in a crowd-sourced survey of the sky. Map of total exposure time for all DECam and Mosaic images (2004 - 2017) on a log scale (top). A Data Lab query of the DES DR1 catalog for blue sources near the known dwarf galaxy Eri III, when spatially filtered, reveals the galaxy as an object density peak (lower right). A Data Lab image cutout of the region (lower left) shows a very low surface brightness collection of blue point sources, confirming that it is a dwarf galaxy.