Detecting scars from the Big Bang
The events surrounding the Big Bang were so cataclysmic that they left an indelible imprint on the fabric of the cosmos. We can detect these scars today by observing the oldest light in the universe. As it was created nearly 14 billion years ago, this light -- which exists now as weak microwave radiation and is thus named the cosmic microwave background (CMB) -- permeates the entire cosmos, filling it with detectable photons.
The NASA/ESA (European Space Agency) Hubble Space Telescope observed one of most massive known galaxy clusters, RX J1347.5-1145, seen in this Picture of the Week, as part of the Cluster Lensing And Supernova survey with Hubble (CLASH). This observation of the cluster, 5 billion light-years from Earth, helped the Atacama Large Millimeter/submillimeter Array (ALMA) in Chile to study the cosmic microwave background using the thermal Sunyaev-Zel'dovich effect. The observations made with ALMA are visible as the blue-purple hues.
Source: ESA [March 02, 2017]