2017_EJRNL_PP_G_H__Schaefer_1.pdf
Terbatas pustaka bosscha
» ITB
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