A significant new discovery in the field of astronomy has revealed that the supernova remnant G278.94+1.35, now named Diprotodon, is much closer and larger than previously thought. Initially believed to be around 8,800 light years away, new research has shown that it is actually located approximately 3,300 light years from Earth. The remnant, which is the result of a massive stellar explosion, spans around 189 by 182 light years in size, a significant reduction from earlier estimates of over 500 light years.

This discovery, led by Miroslav D. Filipović and his team at Western Sydney University, involved observations made using the Australian Square Kilometer Array Pathfinder (ASKAP) as part of the ASKAP-Evolutionary Map of the Universe project. The remnant's nearly circular shape and expansive nature are indicative of its ongoing expansion, which is a characteristic feature of supernova remnants in the radiative phase of evolution.

Named after the extinct giant marsupial Diprotodon, the discovery aims to raise awareness about Australia's prehistoric megafauna and the importance of conservation. The remnant is significant for providing new insights into the dynamics of supernova remnants, particularly regarding their formation, expansion, and energy release. The progenitor star of the remnant is believed to have been about 15 times the mass of the Sun, and the explosion released approximately 500 quindecillion ergs of kinetic energy. The study of Diprotodon thus contributes valuable knowledge to the broader understanding of the lifecycle of massive stars and their explosive end stages.