HR 6135

HR 6135

Observation data Epoch J2000      Equinox J2000
Constellation	Apus
Right ascension	16^h 34^m 19.34618^s[1]
Declination	−70° 59′ 17.1680″[1]
Apparent magnitude (V)	5.50[2]
Characteristics
Evolutionary stage	red giant branch[1]
Spectral type	K0.5 IIb CN1[3]
B−V color index	1.235±0.004[2]
Astrometry
Radial velocity (Rv)	−9.37±0.14[1] km/s
Proper motion (μ)	RA: −15.427±0.036[1] mas/yr Dec.: −11.056±0.046[1] mas/yr
Parallax (π)	3.2585 ± 0.0357 mas[1]
Distance	1,000 ± 10 ly (307 ± 3 pc)
Absolute magnitude (MV)	−1.45[2]
Details
Mass	5.4[1] M☉
Radius	49[1] R☉
Luminosity	843[1] L☉
Surface gravity (log g)	1.66[1] cgs
Temperature	4,592[1] K
Rotational velocity (v sin i)	4.2[4] km/s
Other designations
CPD−70°2256, FK5 3306, GC 22212, HD 148488, HIP 81141, HR 6135, SAO 257409[5]
Database references
SIMBAD	data

HR 6135 is single^[6] star in the southern constellation of Apus, less than a degree from the northern constellation border with Triangulum Australe. Its declination of −70° 59.3′ puts it just within 20 degrees of the southern celestial pole. The star has an orange hue and is faintly visible to the naked eye with an apparent visual magnitude of 5.50,^[2] making it the 12th-brightest star in the constellation. It is located at a distance of approximately 1,000 light years from the Sun based on parallax, but is drifting closer with a radial velocity of −9.5 km/s.^[1] It has an absolute magnitude of −1.45.^[2]

This is an aging bright giant with a stellar classification of K0.5IIbCN1,^[3] where the suffix notation indicates an anomalous overabundance of cyanogen in the spectrum. It is a mild barium star, which may indicate it is on the asymptotic giant branch stage of its evolution.^[7] The star has expanded to 49 times the radius of the Sun and is radiating 843 times the Sun's luminosity from its swollen photosphere at an effective temperature of 4,592 K.^[1]

References

1. Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
2. Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. S2CID 119257644.
3. Keenan, Philip C.; McNeil, Raymond C. (1989). "The Perkins catalog of revised MK types for the cooler stars". The Astrophysical Journal Supplement Series. 71: 245. Bibcode:1989ApJS...71..245K. doi:10.1086/191373.
4. De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. eISSN 1432-0746. ISSN 0004-6361.
5. "HD 148488". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-08-04.
6. Eggleton, P. P.; Tokovinin, A. A. (September 2008). "A catalogue of multiplicity among bright stellar systems". Monthly Notices of the Royal Astronomical Society. 389 (2): 869–879. arXiv:0806.2878. Bibcode:2008MNRAS.389..869E. doi:10.1111/j.1365-2966.2008.13596.x. S2CID 14878976.
7. Gomez, A. E.; et al. (1997). "Absolute magnitudes and kinematics of barium stars". Astronomy and Astrophysics. 319: 881. Bibcode:1997A&A...319..881G.