Never-Before-Seen Supernova Proves Crucial Fact On The Interior Of Stars

Researchers report the discovery of supernova SN2021yfj, a first-of-its-kind supernova that changes our knowledge about stars' evolution and death, while confirming something that has been suspected for a very long time. Massive, evolved stars are like onions and ogres: they have layers. The rest of this article is behind a paywall. Please sign in or subscribe to access the full content.

Stars start by fusing hydrogen into helium; while they do that, they are in the main sequence. Once the hydrogen in the core is gone, there’s a mini-collapse, which leads to increased temperatures in the core and the fusing of helium into heavier elements. The star also swells up into a red giant star whose outer layers are loosely held together by gravity. The more massive stars continue fusing into heav