One Galaxy Cluster, Through Hubble’s Eyes, Can Show Us The Entire Universe
“There’s more gravity than the gas can provide, showing the presence of non-baryonic dark matter.
But all the mass, combined, contributes to gravitational lensing.
The bending of space stretches and magnifies the light from galaxies behind the cluster.
This is the whole purpose of the joint Hubble/Spitzer RELICS program, highlighted by this galaxy cluster.”
Want to see the most distant galaxy in the Universe? You don’t simply need the world’s greatest telescopes; you also need an assist from gravity. Galaxy clusters provide the largest gravitational sources in the Universe, thereby providing the largest natural magnification enhancements through gravitational lensing. While the internal dynamics of the galaxies tell us that there must be dark matter present, and that dark matter is something other than normal (atom-based) matter, the overall gravitational effects enhance any telescope-based views of the Universe. The joint Hubble/Spitzer RELICS program is imaging 41 of these massive galaxy clusters, hoping to magnify ultra-distant galaxies more distant than any we’ve ever seen before. When the James Webb Space Telescope comes online, these will be the places where our greatest target candidates for “most distant galaxy in the Universe” will come from.