NO Aurigae explained

NO Aurigae is a pulsating variable star in the constellation Auriga. It is an unusually-luminous asymptotic giant branch star about 3,500 light years away.

Variability

NO Aurigae is listed in the General Catalogue of Variable Stars as a slow irregular variable, indicating that no regularity could be found in the brightness variations. Other studies have suggested possible periods of 102.1, 173, and 226 days, and would classify it as a semiregular variable star.[1] The maximum visual magnitude range is 6.05–6.50.[1]

Properties

Most studies of NO Aurigae treat it as a red supergiant member of the Auriga OB1 stellar association at about 1.4 kpc.[2] [3] On this basis it would have a luminosity around and a radius around .[2]

NO Aurigae is an MS star, intermediate between spectral type M and S. These are typically Asymptotic Giant Branch stars which can appear with supergiant spectra due to their large size and low mass.[4] Possible detection of Technetium in the spectrum is a symptom of the third dredge-up which occurs only in late AGB stars.[3]

External links

Notes and References

  1. 2006SASS...25...47W. The International Variable Star Index (VSX). The Society for Astronomical Sciences 25th Annual Symposium on Telescope Science. Held May 23–25. 25. 47. Watson. C. L.. 2006.
  2. 2011A&A...526A.156M. 1010.5369. The mass-loss rates of red supergiants and the de Jager prescription. Astronomy and Astrophysics. 526. A156. Mauron. N.. Josselin. E.. 2011. 10.1051/0004-6361/201013993. 119276502.
  3. 2007A&A...469..671J. 0705.0266. Atmospheric dynamics and the mass loss process in red supergiant stars. Astronomy and Astrophysics. 469. 2. 671. Josselin. E.. Plez. B.. 2007. 10.1051/0004-6361:20066353. 17789027.
  4. 2008A&A...488..675G. Infrared photometry and evolution of mass-losing AGB stars. II. Luminosity and colors of MS and S stars. Astronomy and Astrophysics. 488. 2. 675–684. Guandalini. R.. Busso. M.. 2008. 10.1051/0004-6361:200809932. 0806.4591 . 14294870.