Hubble probes merging galaxy clusters combining to form powerful gravitational lenses

While the James Webb Space Telescope is capturing headlines on a near-daily basis, its famous predecessor – the Hubble Space Telescope – remains in the forefront of optical astronomy as seen in this view of at least two galaxy clusters in the process of merging. In a project called “Monsters in the Making,” Hubble’s Wide Field Camera 3 and the Advanced Camera for Surveys studied a throng of galaxies known as eMACS J1353.7+4329, located about eight billion light years from Earth in the constellation Canes Venatici. The resulting image shows the crowded field of galaxies and the first hints of gravitational lensing, arcs of distorted light from background galaxies that are magnified by the combined gravity of the foreground cluster. The Monsters in the Making project is designed to help lay the groundwork for future gravitational lensing studies by Webb and other next-generation telescopes.

The arc-like structure to the left of the bright star at upper right is the light from a more distant background galaxy, distorted and magnified by the combined gravity of merging galaxy clusters in the foreground. Image: ESA/Hubble & NASA, H. Ebeling