Interstellar dust and extinction.
Abstract
It is noted that the term 'interstellar dust' refers to materials with rather different properties, and that the mean extinction law of Seaton (1979) or Savage and Mathis (1979) should be replaced by the expression given by Cardelli et al. (1989), using the appropriate value of total-to-selective extinction. The older laws were appropriate for the diffuse ISM but dust in clouds differs dramatically in its extinction law. Dust is heavily processed while in the ISM by being included within clouds and cycled back into the diffuse ISM many times during its lifetime. Hence, grains probably reflect only a trace of their origin, although meteoritic inclusions with isotopic anomalies demonstrate that some tiny particles survive intact from a supernova origin to the present.
- Publication:
-
Annual Review of Astronomy and Astrophysics
- Pub Date:
- 1990
- DOI:
- Bibcode:
- 1990ARA&A..28...37M
- Keywords:
-
- Cosmic Dust;
- Interstellar Extinction;
- Interstellar Matter;
- Emission Spectra;
- Far Ultraviolet Radiation;
- Milky Way Galaxy;
- Near Infrared Radiation;
- Polarized Radiation;
- Silicates;
- Astrophysics