An Astronomical Vision Test, ESO 540-030

Peering into the depths of space, Hubble has imaged the nearby but faint dwarf galaxy ESO 540-030 appearing as a swarm of uniformly dim pinpoints of light. ESO 540-030 is just over 11 million light-years distant and is part of the Sculptor Group of galaxies. This collection with about a dozen, loosely bound members, is close in space to the Local Group of galaxies of which the Milky Way is a part. Due to its proximity, the Sculptor Group contains some of the brightest galaxies in the southern skies, although ESO 540-030 is not one of these; dwarf galaxies generally have low surface brightness, which make them difficult to locate and study. In the background of the image, many different types of galaxies — spirals, barred spirals, ellipticals, and irregulars — are all on display due to the sensitive detectors within the ACS.