IRAS 20056+1834 : a G star reflects on its past.
Abstract
Spectroscopic and photometric observations of the IRAS source 20056+1834 are discussed. The optical counterpart has a visual magnitude of 12.5 and its spectrum appears to be that of a G0 supergiant on which are superimposed very strong, broad (140 km s-1 FWHM) Na D emission lines. Photometrically the object varies with a low amplitude and a characteristic time-scale of 50 days. A model is proposed in which a mass-losing star is obscured from direct view by a thick dust cloud so that its photosphere is seen only in reflection. The Na D emission is produced by resonantly scattered starlight in the expanding, unobscured stellar envelope.
- Publication:
-
Monthly Notices of the Royal Astronomical Society
- Pub Date:
- August 1988
- DOI:
- 10.1093/mnras/233.4.697
- Bibcode:
- 1988MNRAS.233..697M
- Keywords:
-
- Infrared Astronomy Satellite;
- Stellar Evolution;
- Stellar Mass;
- Stellar Mass Ejection;
- Stellar Spectrophotometry;
- Supergiant Stars;
- H Alpha Line;
- Stellar Spectra;
- Ubv Spectra;
- Astronomy