1 March 2023
Behold! the traces of the first-ever supernova recorded in history!
Using the Dark Energy Camera (DEC) built on the Víctor M. Blanco 4-meter Telescope in Chile, a team of astronomers captured the glowing remains of the supernova SN 85 that burst more than 1800 years ago. Astronomers call this remaining structure RCW 86.
SN 85 was the end game of a dying white-dwarf star. It took place at a location more than 8000 light-years away from our Earth in the direction of Alpha Centauri, between the constellations of Circinus and Centaurus. Over the years, the structure expanded and evolved into RCW 86. It has a ring shape and cloud-like features that appear to be flying from a central point. Like a balloon scattering into pieces when popped!
Astronomers were able to create this rare image of the supernova remains with the aid of the wide field view of the Dark Energy Camera. Until now, it was challenging for astronomers to understand how the structure evolved over time and how it expanded so fast.
By studying the X-ray data, astronomers found the presence of large amounts of iron - a clear sign showing that the explosion was a Type Ia supernova. Astronomers now got a better idea of how RCW 86 formed. As the white-dwarf speedily and violently ate the materials from its fellow star, the high-velocity winds from the white-dwarf pushed all the gas and dust surrounding the stars outwards. The process created some space in between, like a cavity (yes like the gross ones in our teeth!). Finally, when the white dwarf made its grand supernova exit, the pieces of star materials got thrown off at a high-velocity. Luckily, the cavity gave these high-velocity materials enough room to expand super quickly, creating the structure that we see today. Voilà!
Using this image, astronomers aim to look deeper into the physics of RCW 86 structure and its formation.
Image: A ring of glowing remains of the first-ever recorded supernova, a white dwarf star that exploded more than 1800 years ago. Credit: CTIO/NOIRLab/DOE/NSF/AURA T.A. Rector (University of Alaska Anchorage/NSF’s NOIRLab), J. Miller (Gemini Observatory/NSF’s NOIRLab), M. Zamani & D. de Martin (NSF’s NOIRLab)
SN 185 was first witnessed by Chinese astronomers in the year 185 C.E. Ancient astronomers called it the ‘guest star’. It was so bright that it remained visible to the naked eye for about 8 months before fading!