Galaxy Cluster RCS2 J2327 and Mass Map

This image shows something spectacular: a massive galaxy cluster that is warping the space around it. The cluster, whose heart is at the center of the frame, is named RCS2 J2327, and is one of the most massive clusters known at its distance or beyond. Massive objects such as RCS2 J2327 have such a strong influence on their surroundings that they visibly warp the space around them. This effect is known as gravitational lensing, and it causes the light from more distant objects to be bent, distorted, and magnified, allowing us to see galaxies that would otherwise be far too distant to detect.