| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Scorpius |
| Right ascension | 17h 50m 11.11291s [1] |
| Declination | −40° 05′ 25.5629″ [1] |
| Apparent magnitude (V) | +4.82 [2] |
| Characteristics | |
| Spectral type | A2 Ib [3] or A6 Ib [4] |
| U−B color index | +0.19 [2] |
| B−V color index | +0.25 [2] |
| Astrometry | |
| Radial velocity (Rv) | −10.2 [5] km/s |
| Proper motion (μ) |
RA: +3.90
[1]
mas/
yr Dec.: −2.42 [1] mas/ yr |
| Parallax (π) | 1.28 ± 0.24 mas [1] |
| Distance | approx. 2,500
ly (approx. 800 pc) |
| Absolute magnitude (MV) | −4.59 [6] |
| Details | |
| Mass | 8.8±0.2 [4] M☉ |
| Luminosity | 5,798 [7] L☉ |
| Temperature | 6,372 [7] K |
| Age | 29.8±4.3 [4] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
ι2 Scorpii, Latinised as Iota2 Scorpii, is a single [9] star in tail of the zodiac constellation of Scorpius. It has an apparent visual magnitude of +4.82, [2] and is visible to the naked eye. Because of parallax measurement errors, the distance to this star is only approximately known: it lies around 2,500 light years away from the Sun. It has a visual companion, a magnitude 11.0 star at an angular separation of 31.60 arcseconds along a position angle of 36°, as of 2000. [10]
In the literature, there are two different stellar classifications for this star: A2 Ib [3] and A6 Ib. [4] In either case it is an A-type supergiant star with an estimated age of 30 [4] million years and a mass 8.8 times that of the Sun. [4] It shines with a luminosity 5,798 times the Sun's from an outer atmosphere that has an effective temperature of 6,372 K. [7] As with other stars of its type, ι2 Scorpii varies slightly in brightness, showing an amplitude of 0.05 in magnitude. [11]
References
- ^ a b c d e van Leeuwen, F. (November 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.
- ^ a b c d Dachs, J.; et al. (November 1982), "UBV-Hβ photometry of luminous stars between l equals 335 deg and l equals 6 deg", Astronomy and Astrophysics Supplement Series, 50: 261–275, Bibcode: 1982A&AS...50..261D.
- ^ a b Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 2, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode: 1978mcts.book.....H.
- ^ a b c d e f 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.
- ^ Evans, D. S. (June 20–24, 1966), Batten, Alan Henry; Heard, John Frederick (eds.), "The Revision of the General Catalogue of Radial Velocities", Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, University of Toronto: International Astronomical Union, Bibcode: 1967IAUS...30...57E.
- ^ 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.
- ^ a b c 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.
- ^ "iot02 Sco". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2016-09-20.
- ^ Eggleton, P. P.; Tokovinin, A. A. (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.
- ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122: 3466–3471, Bibcode: 2001AJ....122.3466M, doi: 10.1086/323920.
- ^ Adelman, S. J.; Albayrak, B. (December 1997), "On the Variability of Early A-Type Supergiants", Information Bulletin on Variable Stars, 4541: 1, Bibcode: 1997IBVS.4541....1A.
External links
- Kaler, James B., "Iota-2 Scorpii", Stars, University of Illinois, retrieved 2016-09-20.
