This observation is part of an ongoing project to fill short gaps in Hubble’s observing schedule by systematically exploring the most massive galaxy clusters in the distant Universe, in the hopes of identifying promising targets for further study with both Hubble and the NASA/ESA/CSA James Webb Space Telescope. This particular galaxy cluster lies at a vast distance of 4.6 billion light-years from Earth. Each year, the Space Telescope Science Institute is inundated with observing proposals for Hubble, in which astronomers suggest targets for observation. Even after selecting only the very best proposals, scheduling observations of all of Hubble’s targets for a year is a formidable task. There is sometimes a small fraction of observing time left unused in Hubble’s schedule, so in its ‘spare time’ the telescope has a collection of objects to explore — including the lensing galaxy cluster shown in this image.
