A new image taken by NASA’s Hubble Space Telescope is helping scientists learn more about a massive galaxy cluster and the invisible matter that makes up the universe. NASA.
The image contains a galaxy cluster called CL0016+1609, also known as MACS J0018.5+1626. It is extremely bright at X-ray wavelengths, and is one of the most extensively studied galaxy clusters at both X-ray and radio wavelengths.
X-ray observations of the cluster revealed that it consists of two clusters of galaxies merging along our line of sight.
The researchers requested observation time using Hubble’s Advanced Camera for Surveys because the data will help them precisely measure the distribution of dark matter in the cluster. This information helps scientists study mergers and understand the role of CL0016+1609 in the large-scale structure of the universe.
Although Hubble cannot see dark matter directly, its infrared and visible-light observations can detect the effects of dark matter’s gravitational lensing on the ordinary matter observed by the telescope.
The image also includes data collected by Hubble’s Wide Field Camera 3 as part of the RELICS (Reionisation Lensing Cluster Survey) observing program. The survey took the first Hubble infrared images of 46 massive galaxy clusters and looked for distant galaxies that had been gravitationally lensed by these clusters.
The RELICS survey identified about 300 high-redshift candidate galaxies that were lensed by galaxy clusters.
One of these distant galaxies appears as a faint vertical arc to the left of the large elliptical galaxies in the center of the image. Another brighter but shorter arc can be seen directly above and to the right of the large elliptical galaxies at the center.
