Chandra Release - October 24, 2019

Visual Description: Abell 1758

An X-ray and optical composite of the galaxy cluster Abell 1758 is presented in this image. The background consists of a black sky with numerous stars scattered across it. The image features two very bright and large clumpy blue spots positioned at 1 o'clock and 5 o'clock. These two blue clumps are two pairs of galaxy clusters, which are massive collections of stars, gas, and dark matter.. They resemble two large raw sapphires floating in a sea of teeny diamonds, and sapphires and rubies. X-rays from NASA's Chandra X-ray Observatory are shown as blue and white, depicting fainter and brighter diffuse emission, respectively. This composite image includes optical data from the Sloan Digital Sky Survey. The Chandra data revealed for the first time a shock wave - similar to the sonic boom from a supersonic aircraft - in hot gas visible with Chandra in the northern pair's collision. From this shock wave, researchers estimate two clusters are moving about 2 million to 3 million miles per hour (3 million to 5 million kilometers per hour), relative to each other.