Gamma Columbae
Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
---|---|
Constellation | Columba |
Right ascension | 05h 57m 32.20958s[1] |
Declination | −35° 16′ 59.8153″[1] |
Apparent magnitude (V) | 4.366 + 12.664[2] |
Characteristics | |
Spectral type | B2.5 IV[3] + G8 V[4] |
U−B color index | −0.66[5] |
B−V color index | −0.18[5] |
Variable type | Candidate SPB[6] |
Astrometry | |
Radial velocity (Rv) | +24.2[7] km/s |
Proper motion (μ) | RA: −3.24[1] mas/yr Dec.: +10.21[1] mas/yr |
Parallax (π) | 3.75 ± 0.18[1] mas |
Distance | 870 ± 40 ly (270 ± 10 pc) |
Absolute magnitude (MV) | −2.76[8] |
Details[6] | |
γ Col A | |
Mass | ±0.3 5.7 M☉ |
Radius | ±0.4 4.8 R☉ |
Luminosity | 2,070[9] L☉ |
Surface gravity (log g) | ±0.20 3.72 cgs |
Temperature | 12,904[9] K |
Rotational velocity (v sin i) | ±16 96 km/s |
Age | ±2.0 23.6[10] Myr |
γ Col B | |
Mass | 0.94[2] M☉ |
Temperature | 5,367[2] K |
Other designations | |
Database references | |
SIMBAD | data |
Gamma Columbae, Latinized from γ Columbae, is a possible[2] wide binary star system in the southern constellation of Columba. It is visible to the naked eye with an apparent visual magnitude of 4.36.[5] Based upon an annual parallax shift of 3.75 mas,[1] it is located roughly 870 light years from the Sun. For early Arabian astronomers, this star, along with ζ CMa, λ CMa, δ Col, θ Col, κ Col, λ Col, μ Col and ξ Col, formed Al Ḳurūd (ألقرد - al-qird), the Apes.[12]
The primary component is an evolved[6] B-type subgiant star with a stellar classification of B2.5 IV.[3] It is a candidate slowly pulsating B-type star with a mean longitudinal magnetic field strength of ±28 G. 94[6] The star has nearly six times the mass of the Sun and close to five times the Sun's girth.[6] It is radiating over 2,000 times the solar luminosity from its outer atmosphere at an effective temperature of 12,904 K.[9] The estimated age of this star is around 24 million years.[10]
The visual magnitude 12.664[2] companion is a G-type main sequence star with a classification of G8 V.[4] It lies at an angular separation of 33.8 arc seconds from the primary, which corresponds to a projected physical separation of 8,844 AU.[2] Despite the young age of these stars, there has been no X-ray emission detected.[2]
References
- 1 2 3 4 5 6 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.
- 1 2 3 4 5 6 7 Gerbaldi, M.; et al. (November 2001), "Binary systems with post-T Tauri secondaries", Astronomy and Astrophysics, 379: 162–184, Bibcode:2001A&A...379..162G, doi:10.1051/0004-6361:20011298.
- 1 2 Hiltner, W. A.; et al. (July 1969), "MK Spectral Types for Bright Southern OB Stars", Astrophysical Journal, 157: 313–326, Bibcode:1969ApJ...157..313H, doi:10.1086/150069.
- 1 2 Huélamo, N.; et al. (July 2000), "X-ray emission from Lindroos binary systems", Astronomy and Astrophysics, 359: 227–241, arXiv:astro-ph/0005348, Bibcode:2000A&A...359..227H.
- 1 2 3 Johnson, H. L.; Iriarte, B.; Mitchell, R. I.; Wisniewskj, W. Z. (1999), "UBVRIJKL photometry of the bright stars", Commission Lunar and Planetary Laboratory, 4: 99, Bibcode:1966CoLPL...4...99J.
- 1 2 3 4 5 Hubrig, S.; et al. (April 2009), "New magnetic field measurements of β Cephei stars and slowly pulsating B stars", Astronomische Nachrichten, 330 (4): 317, arXiv:0902.1314, Bibcode:2009AN....330..317H, doi:10.1002/asna.200811187.
- ↑ Wilson, R. E. (1953), General Catalogue of Stellar Radial Velocities, Carnegie Institution for Science, Bibcode:1953GCRV..C......0W, LCCN 54001336.
- ↑ 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.
- 1 2 3 McDonald, I.; et al. (2012). "Fundamental Parameters and Infrared Excesses of Hipparcos Stars". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–57. arXiv:1208.2037. Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x.
- 1 2 Tetzlaff, N.; et al. (2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410: 190, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x.
- ↑ "gam Col -- Variable Star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2016-12-19.
- ↑ Davis Jr., G. A. (October 1944), "The Pronunciations, Derivations, and Meanings of a Selected List of Star Names", Popular Astronomy, 18: 14, Bibcode:1944PA.....52....8D.
External links
- Kaler, James B. (January 29, 2016), "Gamma Columbae", STARS, University of Illinois, retrieved 2016-12-21.