Elliptical galaxy NGC474

Figure 1. Images of the elliptical galaxy NGC474. 91 million light-years away, this galaxy has a complex of shells and streamers roughly 200,000 light-years across, caused by a collision with a smaller galaxy that has likely occurred with the last 1 billion years. The inset shows a neighbouring galaxy that appears to be in the act of consuming a smaller flat galaxy. The left-hand image is a 1-hour exposure using the C28 0.7-m telescope described in the study. The centre image is a 21.5-hour exposure from the Irida Observatory, using a 30-cm photographic telescope; the right-hand image is from the 3.6-m Canada-France Hawaii Telescope on Maunakea. Centre and right-hand panels are courtesy of Prof P. Duc and Astronomy & Astrophysics. The full image spans roughly the diameter of the full Moon as seen on the sky.