to the passage below and then answer the question afterwards in the same language as the passage: passage: one model for the formation of this category of supernova is a close binary star system. the progenitor binary system consists of main sequence stars, with the primary possessing more mass than the secondary. being greater in mass, the primary is the first of the pair to evolve onto the asymptotic giant branch, where the star's envelope expands considerably. if the two stars share a common envelope then the system can lose significant amounts of mass, reducing the angular momentum, orbital radius and period. after the primary has degenerated into a white dwarf, the secondary star later evolves into a red giant and the stage is set for mass accretion onto the primary. during this final shared-envelope phase, the two spiral stars in closer together as angular momentum. during this final shared-envelope phase, the two spiral stars in closer together as angular momentum. during this final shared-envelope phase, the two spiral stars evolve into a red giant and the stage is
Àlàfo Chandrasekhar