The Green Bean galaxy J2240

CFHT color image, taken in g,r, and i filters, of J2240. The very strong [OIII] emission leads to the peculiar green color of the galaxy near the center of the field. In this object the ultra-luminous narrow-line region (NLR) is as large as the entire object, 130,000 light-years across. The object is located some 3.7 billion light-years distant and the galactic nucleus doesn’t appear very active in the image, contradicting the high [OIII] luminosity discussed in this story.