“Caught in the act”1 reads the news headline for the first-ever observation of a predicted exploding star. The NASA/ESA Hubble Space Telescope captured the image of the first-ever predicted supernova as shown in the image below (bottom right), compared against an image from months earlier (top right). The reappearance of the Refsdal supernova was calculated from different models of the galaxy cluster whose immense gravity is warping the supernova’s light.
This image composite shows the search for the supernova, nicknamed Refsdal, using the NASA/ESA Hubble Space Telescope. The left image shows a part of the deep field observation of the galaxy cluster MACS J1149.5+2223 from the Frontier Fields program. The circle indicates the predicted position of the newest appearance of the supernova. To the lower right the Einstein Cross event from late 2014 is visible. The top right image shows observations by the Hubble Space Telescope from October 2015, taken at the beginning of observation program to detect the newest appearance of the supernova. The lower right image shows the discovery of the Refsdal supernova on 11 December 2015, as predicted by several different models. Credit: NASA/ESA.