12 Scorpii
12 Scorpii is a probable triple star[2] system in the zodiac constellation of Scorpius, located about 300 light years away from the Sun. It has the Bayer designation c1 Scorpii; 12 Scorpii is the Flamsteed designation. This system is faintly visible to the naked eye with a combined apparent visual magnitude of 5.67.[2] It is a probable (82% chance) member of the Sco OB2 moving group.[8]
| Observation data Epoch J2000.0 Equinox J2000.0 | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 16h 12m 16.039s[1] |
| Declination | −28° 25′ 02.31″[1] |
| Apparent magnitude (V) | 5.67 (5.79 + 7.9 + 8.13)[2] |
| Characteristics | |
| Spectral type | B9V[3] + K7.9XR? + F3V[2] |
| U−B color index | −0.19[4] |
| B−V color index | +0.01[4] |
| Astrometry | |
| Radial velocity (Rv) | −0.2±1.8[5] km/s |
| Proper motion (μ) | RA: −23.68±0.76[1] mas/yr Dec.: −42.44±0.69[1] mas/yr |
| Parallax (π) | 10.75 ± 0.80 mas[1] |
| Distance | 300 ± 20 ly (93 ± 7 pc) |
| Absolute magnitude (MV) | +0.56[6] |
| Details | |
| 12 Sco A | |
| Mass | 2.939±0.088[6] M☉ |
| Luminosity | 91[6] L☉ |
| Temperature | 11,402[6] K |
| Age | 150[6] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
The magnitude 5.79[2] primary component is a B-type main-sequence star with a stellar classification of B9V.[3] This star is 150 million years old with three times the mass of the Sun. It is radiating 91 times the Sun's luminosity from its photosphere at an effective temperature of 11,402 K.[6] At an angular separation of 0.20″ is a K7.9 type secondary companion, a possible X-ray source. The third component is an F-type main-sequence star of class F3V and magnitude 8.13, located at a separation of 3.84″.[2]
References edit
- ^ a b c d e 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. S2CID 18759600. Vizier catalog entry
- ^ a b c d e f 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.
- ^ a b Houk, N.; Swift, C. (1999). "Michigan catalogue of two-dimensional spectral types for the HD Stars, Vol. 5". Michigan Spectral Survey. 5. Bibcode:1999MSS...C05....0H.
- ^ a b Nicolet, B. (1964). "Catalogue of homogeneous data in the UBV photoelectric photometric system". Astronomy and Astrophysics Supplement Series. 34: 1–49. Bibcode:1978A&AS...34....1N.
- ^ Gontcharov, G. A. (2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. S2CID 119231169.
- ^ a b c d e f Hubrig, S.; et al. (June 2001), "Search for low-mass PMS companions around X-ray selected late B stars", Astronomy and Astrophysics, 372: 152–164, arXiv:astro-ph/0103201, Bibcode:2001A&A...372..152H, doi:10.1051/0004-6361:20010452, S2CID 17507782.
- ^ "2 Sco". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-03-23.
- ^ Rizzuto, Aaron; Ireland, Michael; Robertson, J. G. (October 2011). "Multidimensional Bayesian membership analysis of the Sco OB2 moving group". Monthly Notices of the Royal Astronomical Society. 416 (4): 3108–3117. arXiv:1106.2857. Bibcode:2011MNRAS.416.3108R. doi:10.1111/j.1365-2966.2011.19256.x. S2CID 54510608.