This image shows the stunning elliptical galaxy Centaurus A. Recently, astronomers have used the NASA/ESA Hubble Space Telescope to probe the outskirts of this galaxy to learn more about its dim halo of stars. The galaxy’s halo of stars has been found to reach much further than expected, extending across 4 degrees in the sky — equivalent to eight times the apparent width of the Moon, or almost twice the width of this image. This image is a composite of images from Digitized Sky Survey 2 (DSS2), the MPG/ESO 2.2-metre telescope, and the NASA/ESA Hubble Space Telescope’s Advanced Camera for Surveys (ACS). The areas probed by Hubble are identified in the annotated version of this image. Hubble’s unique capabilities allowed astronomers to analyse the faint stars in the halo.