Abstract
ζ Aurigae is an eclipsing binary star system with a property shared by only a few other systems. It consists of two stars in orbit around one another: a cool supergiant star (spectral type K2 II) and a hot main sequence (spectral type B8 v) star. The supergiant star is nearly 200 times larger than the Sun, while the main sequence star is only about seven times larger than the Sun. The Earth lies in the orbital plane of the two stars, and thus they periodically eclipse one another. When the relatively small B star goes into eclipse behind the cool supergiant star, its light passes through extended outer gaseous layers—the outer atmosphere—of the cool star. Thus the B star is an astrophysical light source which serves as a probe of the atmosphere of the K star. The eclipses, which occur every 972 days, have been well studied at visible wavelengths1,2. We report here IUE observations of the ζ Aur stellar system carried out between September 1979 and January 1980. A preliminary look at the data shows the advantage of UV observations of the system. There is strong evidence for cool, outflowing material near the primary star and hotter material farther from the primary perhaps in a shockwave. The onset of the atmospheric phase of the eclipse of the system—difficult to predict because of the irregularities of the supergiant atmosphere—began between 15 September and 1 November 1979.
This is a preview of subscription content, access via your institution
Access options
Subscribe to this journal
Receive 51 print issues and online access
$199.00 per year
only $3.90 per issue
Buy this article
- Purchase on Springer Link
- Instant access to full article PDF
Prices may be subject to local taxes which are calculated during checkout
Similar content being viewed by others
References
Wilson, O. C. in Stars and Stellar Systems Vol. 6 (ed. Greenstein. J. L.) 436–464 (University of Chicago Press, 1960).
Wright, K. O. in Vistas in Astronomy Vol. 12, 147–182 (Pergamon, New York, 1970).
Doschek, G. A., Feldman, J., Cohen, L. Astrophys. J. Suppl. 33, 101–111 (1977).
Cohen, L., Feldman, J. & Doschek, G. A. Astrophys. J. Suppl. 37, 393–405 (1978).
Author information
Authors and Affiliations
Rights and permissions
About this article
Cite this article
Chapman, R. IUE observations of the atmospheric eclipsing binary system ζ Aurigae. Nature 286, 580–582 (1980). https://doi.org/10.1038/286580a0
Received:
Accepted:
Issue Date:
DOI: https://doi.org/10.1038/286580a0
Comments
By submitting a comment you agree to abide by our Terms and Community Guidelines. If you find something abusive or that does not comply with our terms or guidelines please flag it as inappropriate.