Benutzerspezifische Werkzeuge


Mass loss




Stars, including our Sun, are not really static objects. In general, there is a perpetual flow of matter from the stellar surface into the interstellar medium called a 'stellar wind'. Such a mass loss is entirely negligible for a star like our Sun. However, during more advanced stages of evolution mass loss becomes the dominant factor which rather abruptly terminates the course of evolution and determines which fraction of the initial stellar mass remains locked up in the extinct remnant, the white dwarf. Though individually observed mass-loss rates are very uncertain, and calculations from first principles still very complicated or even unpossible, the total mass lost, the mass budget, is accessible to observations and indicates that e.g. a 7 Msun star will loose about 6 Msun by a wind before it turns into a white dwarf of about 1 Msun.




wbild2.gif AGB Mass Loss History & Haloes around Planetary Nebulae