We watched a red supergiant explode to ordinary type II supernova

[Tom.G]

First suspicious activity of SN 2020tlf (in the NGC 5731 galaxy) was noted 130 days prior, which prompted astronomers to keep an eye on it.

"This is a breakthrough in our understanding of what massive stars do moments before they die," said lead study author Wynn Jacobson-Galán, a National Science Foundation Graduate Research Fellow at University of California, Berkeley, in a statement.

Popular version:
https://www.cnn.com/2022/01/06/world/red-supergiant-star-supernova-scn/index.html

Technical report in "The Astrophysical Journal":
https://iopscience.iop.org/article/10.3847/1538-4357/ac3f3a

EDIT: See more in post #3 below.

Cheers,
Tom

 

[sophiecentaur]

HA HA this was almost eclipsed by that old prima donna JST. We have to be thankful that someone was still running the shop whilst we were all focussed on L2.

 

[Tom.G]

Here is a time-lapse video:
https://cbsnews2.cbsistatic.com/hub/i/2022/01/06/09db54f0-0c2c-4808-b333-587a6d99c965/red-giant.gif

(above from this article:
https://www.cbsnews.com/news/red-supergiant-star-supernova-film-image-death/)

 

[JLowe]

Wonder what exactly it was doing before the superno a. All i read was "broght radiation".

 

[berkeman]

Here is a time-lapse rendering video:
https://cbsnews2.cbsistatic.com/hub/i/2022/01/06/09db54f0-0c2c-4808-b333-587a6d99c965/red-giant.gif

Fixed it for you...