JERUSALEM, Aug. 20 (Xinhua) -- An international team of scientists has identified a new type of supernova that provides a rare look inside massive stars, Israel's Weizmann Institute of Science said on Wednesday.
The study, published in Nature and featured on its cover, describes the supernova, SN2021yfj, as unusually rich in heavy elements such as silicon, sulfur and argon. Most supernovae typically reveal only lighter elements like hydrogen and helium.
Massive stars are thought to have an onion-like structure, with light elements in the outer layers and heavier ones deeper inside, ending with an iron core. Until now, observations of supernovae had mostly shown only the outer shells.
In this case, researchers found evidence that the star lost its outer layers before exploding, exposing its deeper interior. Analysis of the light from the blast showed a spectrum dominated by heavy elements, suggesting the core had been laid bare.
"This is the first time we have seen a star that was essentially stripped to the bone," said lead author Steve Schulze. "It shows us how stars are structured and proves they can be stripped all the way down and still produce a brilliant explosion visible from very far away."
The team discovered SN2021yfj in September 2021. They said the findings provide rare, direct evidence of the layered structure of massive stars and challenge existing theories about how they shed mass before collapsing. The results could also help explain the origin of many of the universe's heavy elements, underscoring the role of giant stars in the cosmic cycle of matter. ■
