Recently Discovered Dwarf Galaxy Donatiello II

The smudge in the center of this image from the Dark Energy Camera (DECam), built by the US Department of Energy, is the elusive dwarf galaxy Donatiello II. It is one of six dwarf galaxies discovered by Italian amateur astronomer Giuseppe Donatiello. Three of them — Donatiello II, III and IV — were tucked away in the DECam images, and are now known to be satellites of the Sculptor Galaxy (NGC 253) (outside the field, to the far right).

DECam is an instrument on the Víctor M. Blanco 4-meter Telescope at Cerro Tololo Inter-American Observatory (CTIO), a Program of NSF NOIRLab. It combines a wide field of view with high sensitivity, meaning that it can scan large swathes of the night sky and also pick out the faint stars making up neighboring dwarf galaxies such as this one.

The Milky Way shares its patch of the Universe with a whole host of small galaxies and star clusters, which help astronomers shed light on the yet-to-be-understood physics of dark matter.