Artist’s impression of the supernova Betelgeuse. Credits: Southern European Observatory / L. Calsada
Astronomers from Liverpool John Moores University and the University of Montpellier have designed an “early warning” system to issue a warning when a massive star is about to end its life in a short time. Supernova explosion. The work was published today (13 October 2022) at the address Royal Astronomical Society Monthly Notices.
In this new study, the researchers determined that massive stars (usually between 8 and 20 solar masses) in the last phase of their life, called the “red giant” phase, would suddenly become about a hundred times fainter in visible light. The last months before he died. This darkening is caused by a sudden build-up of material around the star, blocking its light.
A red giant star is a star of spectral type K or M with a giant luminosity class (Yerkes class I). In terms of size, they are the largest stars in the universe. However, it is not the most massive or bright. Betelgeuse and Antares are the brightest and most famous red giants.
Until now, it was not known how long it would take for the stars to synthesize this substance. For the first time, scientists simulated what a red giant planet might look like when embedded in a pre-explosion “cocoon”.
Old telescope records show that there was indeed an image of the star exploding about a year after the image was captured. Stars appear naturally in these images, which means they cannot form a theoretical cocoon. This indicates that the cocoons are assembled in less than a year, which is considered to be very fast.
“Dense matter almost completely darkens the star, making it 100 times fainter in the visible part of the spectrum,” said Benjamin Davies of Liverpool John Moores University, lead author of the paper. This means that the day before the star’s explosion, you probably won’t be able to see it’s there. “He added,” Up until now, we’ve only been able to get detailed observations of the supernova a few hours after it actually is. verified. With this early warning system, we can be prepared to monitor it in real time, to point the best telescopes in the world at their predecessors. the stars, and here they are completely dispersed in front of them ». our eyes. “
Reference: “The Upcoming Explosion: Rise of the Red Giant on the Threat of Core Collapse” by Ben Davies, Bertrand Blaise and Mike Pettrault, 13 Oct 2022, Available here. Royal Astronomical Society Monthly Notices.
DOI: 10.1093 / mnras / stac2427
