Chandra X-ray and VLT Optical Images of JKCS041
These images are of the most distant galaxy cluster yet detected. On the left, is the X-ray image from NASA's Chandra X-ray Observatory, and on the right is the optical image from the Very Large Telescope (VLT), that also includes optical and infrared data from the Digitized Sky Survey. This record-breaking object, known as JKCS041, is observed as it was when the Universe was just one quarter of its current age. X-rays from Chandra are displayed as the diffuse blue region, while the individual galaxies in the cluster are seen in white in the VLT's optical data.
(Credit: X-ray: NASA/CXC/INAF/S.Andreon et al Optical: DSS; ESO/VLT)