Core Insights - The recent astronomical study published in the journal "Nature" reveals new insights into the internal structure of stars through the observation of a rare cosmic event, specifically a supernova explosion [1][2] - The research challenges existing theories regarding the mechanisms of mass loss and stripping in massive stars, suggesting the presence of a rare mechanism [2] Summary by Sections Study Findings - Astronomers observed supernova SN 2021yfj, which revealed that the progenitor star had shed most of its outer layers, exposing its internal stellar layers during the explosion [1] - A thick, massive shell rich in silicon and sulfur was detected, which was expelled shortly before the supernova event, alongside unexpected helium presence [1] Theoretical Implications - The findings directly confirm theoretical predictions regarding the shell structure of massive stars, extending to layers rich in silicon and sulfur, thus addressing the mystery surrounding the end of massive star life [2]

Core Insights - A rare cosmic event involving a massive star has been reported, revealing insights into the life cycle of massive stars and confirming predictions about their end-of-life structures [1][2] Group 1: Stellar Evolution - The study provides new insights into stellar evolution, particularly regarding the end of life for massive stars, which can be tens to hundreds of times the mass of the Sun [1] - There are existing theoretical discrepancies regarding the "birth" and "death" of massive stars, particularly concerning their shell structures composed of different elements [1] Group 2: Supernova Observation - Researchers from Northwestern University observed supernova 2021yfj, where the progenitor star appeared to have shed most of its outer layers, revealing its internal structure during the explosion [1] - A thick, massive shell rich in silicon and sulfur was detected, which was expelled shortly before the supernova, alongside unexpected helium presence [1] Group 3: Theoretical Implications - The exposed internal structure of the star challenges existing theories on mass loss and shedding mechanisms in massive stars, suggesting the involvement of a rare mechanism [1]