HR 4049
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Antlia |
| Right ascension | 10h 18m 07.59s[1] |
| Declination | –28° 59′ 31.2″[1] |
| Apparent magnitude (V) | 5.53 |
| Characteristics | |
| Spectral type | B9.5Ib-II |
| B−V color index | 0.23 |
| Variable type | Post-AGB Star |
| Astrometry | |
| Radial velocity (Rv) | -33 km/s |
| Proper motion (μ) | RA: –15.86 ± 0.32[1] mas/yr Dec.: 10.85 ± 0.38[1] mas/yr |
| Parallax (π) | 1.23 ± 0.36[1] mas |
| Distance | approx. 2,700 ly (approx. 800 pc) |
| Absolute magnitude (MV) | -3.68 |
| Details | |
| Mass | 1.2 M☉ |
| Radius | 15.1 [2] R☉ |
| Luminosity | 3823 L☉ |
| Temperature | 11500 K |
| Other designations | |
| Database references | |
| SIMBAD | data |
HR 4049, also known as HD 89353 and AG Antliae, is a post-asymptotic-giant-branch star in the constellation Antlia. A very metal-poor star,[3] it is surrounded by a thick unique circumbinary disk enriched in several molecules.[4] With an apparent magnitude of 5.53, the star can readily be seen under ideal conditions.[5] The star, located approximately 813 parsecs (2,650 ly) distant,[5] has been found to be a binary star;[6] however, likely the most unique feature about this star is its peculiar spectrum. The star appears, based on its spectrum in the Balmer series, to be a blue supergiant, although in reality it is an old low-mass star on the post-AGP phase of its life.[7] The star is also undergoing intense mass-loss[8] and is a unique variable, ranging between magnitudes 5.29 and 5.83 with a period of 429 days[9]
References
- 1 2 3 4 5 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. arXiv:0708.1752. Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357.Vizier catalog entry
- ↑ Bakker; et al. (1998). "Spectral variability of the binary HR 4049". Astronomy and Astrophysics 336 (1): 263–275. arXiv:astro-ph/9802120. Bibcode:1998A&A...336..263B.
- ↑ Takeda, Y.; Parthasarathy, M.; Aoki, W.; Ita, Y.; Nakada, Y.; Izumiura, H.; Noguchi, K.; Takada-Hidai, M.; Sato, B.; Tajitsu, A.; Honda, S.; Kawanomoto, S.; Ando, H.; Karoji, H. (2002). "Detection of Zinc in the Very Metal-Poor Post-AGB Star HR 4049". Publications of the Astronomical Society of Japan 54 (5): 765. doi:10.1093/pasj/54.5.765.
- ↑ Malek, S. E.; Cami, J. (2014). "The Gas-Rich Circumbinary Disk of Hr 4049. I. A Detailed Study of the Mid-Infrared Spectrum". The Astrophysical Journal 780: 41. doi:10.1088/0004-637X/780/1/41.
- 1 2 "AG Antliae". SIMBAD Astronomical Database. Centre de Données astronomiques de Strasbourg. Retrieved 15 June 2014.
- ↑ Acke, B.; Degroote, P.; Lombaert, R.; De Vries, B. L.; Smolders, K.; Verhoelst, T.; Lagadec, E.; Gielen, C.; Van Winckel, H.; Waelkens, C. (2013). "Amorphous carbon in the disk around the post-AGB binary HR 4049". Astronomy & Astrophysics 551: A76. doi:10.1051/0004-6361/201219282.
- ↑ Waelkens, C.; Lamers, H.; Waters, R. (September 1987). "HR 4049 - an old low-mass star disguised as a young massive supergiant". ESO Messenger 49: 29–32. Bibcode:1987Msngr..49...29W.
- ↑ Geballe, T. R.; Noll, K. S.; Whittet, D. C. B.; Waters, L. B. F. M. (1989). "Unusual features of the 1-4 micron spectrum of HR 4049". The Astrophysical Journal 340: L29. doi:10.1086/185431.
- ↑ VSX (4 January 2010). "AG Antliae". The International Variable Star Index. American Association of Variable Star Observers. Retrieved 15 June 2013.
External links
- The Spatial Distribution of Grains Around the Dual Chemistry Post-AGB Star
- Synthetic post-AGB evolution
- Non-linear radiative models of post-AGB stars: Application to HD 56126
- Post-AGB stars as testbeds of nucleosynthesis in AGB stars
- The post-AGB evolution of AGB mass loss variations
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