digilib@itb.ac.id +62 812 2508 8800

2017_EJRNL_PP_G_H__Schaefer_1.pdf
Terbatas pustaka bosscha
» ITB

Stars that have more than about nine times the mass of our Sun lose considerable mass throughout their lifetimes as a result of stellar winds, a process that provides elements for the next generation of stars and for planet formation. On page 310, Ohnaka et al.1 present the first two-dimensional map to depict the velocity of gas across the surface of a red supergiant — a massive star at a late stage of its evolution. The map shows large clumps of upwelling and downdraughting gas in the star’s outer atmosphere, and suggests that convection alone cannot be responsible for lifting material away from the stellar surface of massive stars as had been thought