Planetary nebulae are a keystone for the understanding of the evolution of stars, for deep insights into the physical processes prevailing in highly excited dilute nebulae, and for the chemical evolution in galaxies. These objects, displaying an intriguing morphology, have a `short' lifetime of a few tens of thousands of years, and have become one of the best studied classes of celestial sources. However, despite large and successful efforts from both the observational and theoretical side, planetary nebulae still keep some of their secrets (like the widely unknown distances) and will undoubtedly also be objects of thorough investigations in the years to come.Beyond the Magellanic Clouds Abundance analyses have been made for one nebula in the dwarf Fornax galaxy in the Local Group (Danziger et al. ... Jacoby aamp; Ford (1986) analysed 3 PNs in M31, at projected distances of 3.5, 18 aamp; 33kpc from the centre. ... R. Haynes aamp; D.K. Milne, p291 Becker, S.A. aamp; Iben, I.: 1979, Ap. J., 232, 831 Becker, S.A. aamp; Iben, I.: 1980, Ap. J., 237, 111 Brocato, E., Matteucci, F ., anbsp;...
|Author||:||R. Weinberger, A. Acker|
|Publisher||:||Springer Science & Business Media - 2012-12-06|