A supernova explosion that happened in Centaurus A. This animation represents about 1.5 years of time, omitting the first frame which is a legacy image from 2010. This all happened a bit more than one month after the initial explosion. What you see here is the fading of the supernova, and then the blueish ring that is a light echo that began to propagate outwards immediately after the initial explosion. Upon closer inspection, a second, fainter light echo seems to appear following the first in the last two frames.
Some processing notes: The telescope never oriented the same way twice when taking observations, resulting in diffraction spikes and the whole PSF of the foreground star being incredibly distracting. I stabilized this quite a bit by both using a stacked median version of the datasets to remove the spikes completely, and then added the 2010 spikes back on to all the frames. Red channel data were missing from the 3rd and 4th frames (second and third brightest images of the fading supernova) so color for that is both guessed and pulled from the 2010 data. I did use a fair amount of clarity and texture filtering from Camera Raw.
Data from the following proposals were used to create this image:
Star Formation in Nearby Galaxies
Light Echoes and the Progenitor of SN 2016adj in Cen A
Light Echoes and the Environments of SNe 2014J and 2016adj
Red: WFC3/UVIS F814W
Green: WFC3/UVIS F547M
Blue: WFC3/UVIS F438W
North is up.