Zeta Circini
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Circinus[1] |
| Right ascension | 14h 54m 42.586s[2] |
| Declination | −65° 59′ 27.978″[2] |
| Apparent magnitude (V) | 6.08[3] |
| Characteristics | |
| Spectral type | B2/3 Vn[4] |
| U−B color index | −0.617[3] |
| B−V color index | −0.073[3] |
| Variable type | SPB[5] |
| Astrometry | |
| Radial velocity (Rv) | −18.0±4.3[6] km/s |
| Proper motion (μ) | RA: −9.071 mas/yr[2] Dec.: −8.227 mas/yr[2] |
| Parallax (π) | 2.3291±0.0529 mas[2] |
| Distance | 1,400 ± 30 ly (429 ± 10 pc) |
| Absolute magnitude (MV) | −1.82[1] |
| Details[5] | |
| Mass | 5.5±1.0 M☉ |
| Radius | 3.8±1.3 R☉ |
| Luminosity | 602[7] L☉ |
| Surface gravity (log g) | 4.03±0.20 cgs |
| Temperature | 16,788 K |
| Rotational velocity (v sin i) | 264±8 km/s |
| Age | 31.6±5.7[8] Myr |
| Other designations | |
| ζ Cir, CD−65°1813, HD 131058, HIP 72965, HR 5539, SAO 252951[9] | |
| Database references | |
| SIMBAD | data |
Zeta Circini is a star located in the southern constellation of Circinus. Its name is a Bayer designation that is Latinized from ζ Circini, and abbreviated Zeta Cir or ζ Cir. With an apparent visual magnitude of 6.08,[3] it is barely visible to the naked eye on a dark night. (According to the Bortle scale, it requires the lighting level of suburban skies or darker to be seen.) The distance to this star, as estimated using an annual parallax shift of 2.33 mas,[2] is around 1,400 light years. It is drifting closer to the Sun with a line of sight velocity component of around −18 km/s.[6]
This is a B-type main sequence star with a stellar classification of B2/3 Vn,[4] where the 'n' suffix indicates broad ("nebulous") absorption lines due to rotation. It is a slowly pulsating B star[5] with a frequency of 0.26877 d−1 and an amplitude of 0.0046 magnitude.[10] The averaged quadratic field strength of the star's longitudinal magnetic field is (1.06±0.46)×10−2 T.[11]
The star is around 32[8] million years old and is spinning rapidly with a projected rotational velocity of 264 km/s.[5] It has an estimated 5.5 times the mass of the Sun and 3.8 times the Sun's radius.[5] Zeta Circini radiates around 602[7] times the solar luminosity from its outer atmosphere at an effective temperature of 16,788 K.[5]
References
[edit]- 1 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 XHIP record for this object at VizieR.
- 1 2 3 4 5 6 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.
- 1 2 3 4 Gutierrez-Moreno, Adelina; Moreno, Hugo (June 1968), "A photometric investigation of the Scorpio-Centaurus association", Astrophysical Journal Supplement, 15: 459, Bibcode:1968ApJS...15..459G, doi:10.1086/190168.
- 1 2 Houk, Nancy; Cowley, A. P. (1979), University of Michigan Catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor, Michigan: Department of Astronomy, University of Michigan, Bibcode:1978mcts.book.....H.
- 1 2 3 4 5 6 Hubrig, S.; et al. (June 2006), "Discovery of magnetic fields in the βCephei star ξ1 CMa and in several slowly pulsating B stars*", Monthly Notices of the Royal Astronomical Society: Letters, 369 (1): L61–L65, arXiv:astro-ph/0604283, Bibcode:2006MNRAS.369L..61H, doi:10.1111/j.1745-3933.2006.00175.x, S2CID 18201908.
- 1 2 de Bruijne, J. H. J.; Eilers, A.-C. (October 2012), "Radial velocities for the HIPPARCOS-Gaia Hundred-Thousand-Proper-Motion project", Astronomy & Astrophysics, 546: 14, arXiv:1208.3048, Bibcode:2012A&A...546A..61D, doi:10.1051/0004-6361/201219219, S2CID 59451347, A61.
- 1 2 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, S2CID 118665352.
- 1 2 Tetzlaff, N.; et al. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society, 410 (1): 190–200, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x, S2CID 118629873.
- ↑ "zet Cir", SIMBAD, Centre de données astronomiques de Strasbourg
- ↑ Koen, Chris; Eyer, Laurent (March 2002), "New periodic variables from the Hipparcos epoch photometry", Monthly Notices of the Royal Astronomical Society, 331 (1): 45–59, arXiv:astro-ph/0112194, Bibcode:2002MNRAS.331...45K, doi:10.1046/j.1365-8711.2002.05150.x, S2CID 10505995.
- ↑ Bychkov, V. D.; et al. (April 2009), "Catalogue of averaged stellar effective magnetic fields - II. Re-discussion of chemically peculiar A and B stars", Monthly Notices of the Royal Astronomical Society, 394 (3): 1338–1350, Bibcode:2009MNRAS.394.1338B, doi:10.1111/j.1365-2966.2008.14227.x, S2CID 120268049.
