3C 275.1, the brightest object in this image, was the first quasar ever discovered at the center of a rich galaxy cluster. Astronomers surmise that 3C 275.1 lies at the center of a rich cluster because there are 32 objects in the sur- rounding area; for a normal patch of sky the number is closer to 8.
3C 275.1ΓÇÖs distance is indicated by the 56 percent redshift of its spectral lines, which corresponds to a time when the universe was about half its present age (roughly 5 billion years ago). Other observations have shown that 3C 275.1 is surrounded by a rotating cloud of gas, an indication that the quasar may be at the center of a giant elliptical galaxy that is still forming. Yet central galaxies in present-day rich galaxy clusters
