Saturday, January 20, 2024

Gone but not forgotten

A galaxy that is flat and misshapen. Above and on its right it is covered by plumes of shining gas and dust, while its centre and left side are more dim and patchy. A trail of dark, dim dust stretches from below the galaxy up and off to the left, where there are three more bright patches. The background around the galaxy is quite dark, with only a few small background galaxies and one star visible. Credit: ESA/Hubble & NASA, A. Filippenko

This image features a relatively small galaxy known as UGC 5189A, which is located about 150 million light-years away in the constellation Leo. This galaxy was observed by Hubble to study a supernova explosion in 2010 known as SN 2010jl. This particular supernova was notable for having been an exceptionally luminous supernova event. In fact, over a period of three years, SN 2010jl released at least 2.5 billion times more visible energy alone than our Sun emitted over the same timeframe across all wavelengths.

Even after supernovae have faded to non-observable levels, it can still be of interest to study the environments where they occurred. This can provide astronomers with valuable information: supernovae can take place for a variety of reasons, and understanding the environments in which they took place can help improve our understanding of the conditions necessary for them to be triggered. Furthermore, follow-up studies after supernovae can improve our understanding of the immediate aftermath of such events, from their potent effects on the gas and dust around them, to the stellar remnants they leave behind.

To this end, UGC 5189A has been observed many times by Hubble since 2010. This image is from data collected in three of the latest Hubble studies of UGC 5189A, which also examined several other relatively nearby galaxies that recently hosted supernovae — ‘relatively nearby’, in this context, meaning roughly 100 million light years away.