Mass loss from red giants: some effects on the interstellar medium.

Mass loss during red-giant phases of intermediate-mass stars is discussed with emphasis on some effects of the red-giant mass-loss processes on the ISM. The relevance of the mean-loss processes for the galactic nucleosynthesis, for the production of interstellar grains, and for planetary nebula is discussed. A relatively restricted number of parameters appears to control their surface composition and ultimate fate. Among the affected astrophysical situations are the frequency of stars igniting carbon in a degenerate core; the production rate, mass distribution, and composition of planetary nebulas; the frequency and period distribution of Mira variables; and the birth rate and mass distribution of white dwarfs.