| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Corona Australis |
| Right ascension | 18h 24m 18.24148s [1] |
| Declination | −44° 06′ 36.9008″ [1] |
| Apparent magnitude (V) | 5.24 [2] |
| Characteristics | |
| Spectral type | B3 V [3] |
| B−V color index | −0.163±0.004 [2] |
| Astrometry | |
| Radial velocity (Rv) | +0.00±7.40 [2] km/s |
| Proper motion (μ) |
RA: −2.949
[1]
mas/
yr Dec.: −23.107 [1] mas/ yr |
| Parallax (π) | 5.9327 ± 0.2341 mas [1] |
| Distance | 550 ± 20
ly (169 ± 7 pc) |
| Absolute magnitude (MV) | −0.63 [2] |
| Details | |
| Mass | 6.2±0.1 [4] M☉ |
| Radius | 3.9 [5] R☉ |
| Luminosity (bolometric) | 1,098 [6] L☉ |
| Temperature | 20,350 [6] K |
| Rotational velocity (v sin i) | 248±12 [7] km/s |
| Age | 103 [8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HR 6875, previously known as Sigma Telescopii, is a single [10] star in the constellation Corona Australis. It has a blue-white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.24. [2] This object is located at a distance of approximately 550 light years from the Sun based on parallax. [1] It is listed as a member of the Sco OB2 association. [7]
This is a hot B-type main-sequence star with a stellar classification of B3 V. [3] It is around 103 [8] million years old and is spinning rapidly with a projected rotational velocity of 248 km/s or perhaps higher. [7] The star has six [4] times the mass of the Sun and about four [5] times the Sun's radius. It is radiating more than a thousand [6] times the luminosity of the Sun from its photosphere at an effective temperature of 20,350 K. [6]
A magnitude 10.13 visual companion is located at an angular separation of 74 ″ along a position angle of 162°. [11]
References
- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv: 1804.09365. Bibcode: 2018A&A...616A...1G. doi: 10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e 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 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 Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (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.
- ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (2) (Third ed.): 521–524, arXiv: astro-ph/0012289, Bibcode: 2001A&A...367..521P, doi: 10.1051/0004-6361:20000451, S2CID 425754.
- ^ a b c d Hohle, M. M.; et al. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten, 331 (4): 349, arXiv: 1003.2335, Bibcode: 2010AN....331..349H, doi: 10.1002/asna.200911355, S2CID 111387483.
- ^ a b c Brown, A. G. A.; Verschueren, W. (1997), "High S/N Echelle spectroscopy in young stellar groups. II. Rotational velocities of early-type stars in SCO OB2", Astronomy and Astrophysics, 319: 811, arXiv: astro-ph/9608089, Bibcode: 1997A&A...319..811B.
- ^ a b Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv: 1606.09028, Bibcode: 2012AstL...38..694G, doi: 10.1134/S1063773712110035, S2CID 119108982.
- ^ "HD 168905". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-14.
- ^ 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.
- ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466, Bibcode: 2001AJ....122.3466M, doi: 10.1086/323920, retrieved 2015-07-22
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Corona Australis |
| Right ascension | 18h 24m 18.24148s [1] |
| Declination | −44° 06′ 36.9008″ [1] |
| Apparent magnitude (V) | 5.24 [2] |
| Characteristics | |
| Spectral type | B3 V [3] |
| B−V color index | −0.163±0.004 [2] |
| Astrometry | |
| Radial velocity (Rv) | +0.00±7.40 [2] km/s |
| Proper motion (μ) |
RA: −2.949
[1]
mas/
yr Dec.: −23.107 [1] mas/ yr |
| Parallax (π) | 5.9327 ± 0.2341 mas [1] |
| Distance | 550 ± 20
ly (169 ± 7 pc) |
| Absolute magnitude (MV) | −0.63 [2] |
| Details | |
| Mass | 6.2±0.1 [4] M☉ |
| Radius | 3.9 [5] R☉ |
| Luminosity (bolometric) | 1,098 [6] L☉ |
| Temperature | 20,350 [6] K |
| Rotational velocity (v sin i) | 248±12 [7] km/s |
| Age | 103 [8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
HR 6875, previously known as Sigma Telescopii, is a single [10] star in the constellation Corona Australis. It has a blue-white hue and is dimly visible to the naked eye with an apparent visual magnitude of 5.24. [2] This object is located at a distance of approximately 550 light years from the Sun based on parallax. [1] It is listed as a member of the Sco OB2 association. [7]
This is a hot B-type main-sequence star with a stellar classification of B3 V. [3] It is around 103 [8] million years old and is spinning rapidly with a projected rotational velocity of 248 km/s or perhaps higher. [7] The star has six [4] times the mass of the Sun and about four [5] times the Sun's radius. It is radiating more than a thousand [6] times the luminosity of the Sun from its photosphere at an effective temperature of 20,350 K. [6]
A magnitude 10.13 visual companion is located at an angular separation of 74 ″ along a position angle of 162°. [11]
References
- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics. 616. A1. arXiv: 1804.09365. Bibcode: 2018A&A...616A...1G. doi: 10.1051/0004-6361/201833051. Gaia DR2 record for this source at VizieR.
- ^ a b c d e 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 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 Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (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.
- ^ a b Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics, 367 (2) (Third ed.): 521–524, arXiv: astro-ph/0012289, Bibcode: 2001A&A...367..521P, doi: 10.1051/0004-6361:20000451, S2CID 425754.
- ^ a b c d Hohle, M. M.; et al. (April 2010), "Masses and luminosities of O- and B-type stars and red supergiants", Astronomische Nachrichten, 331 (4): 349, arXiv: 1003.2335, Bibcode: 2010AN....331..349H, doi: 10.1002/asna.200911355, S2CID 111387483.
- ^ a b c Brown, A. G. A.; Verschueren, W. (1997), "High S/N Echelle spectroscopy in young stellar groups. II. Rotational velocities of early-type stars in SCO OB2", Astronomy and Astrophysics, 319: 811, arXiv: astro-ph/9608089, Bibcode: 1997A&A...319..811B.
- ^ a b Gontcharov, G. A. (November 2012), "Spatial distribution and kinematics of OB stars", Astronomy Letters, 38 (11): 694–706, arXiv: 1606.09028, Bibcode: 2012AstL...38..694G, doi: 10.1134/S1063773712110035, S2CID 119108982.
- ^ "HD 168905". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2018-07-14.
- ^ 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.
- ^ Mason, B. D.; et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal, 122 (6): 3466, Bibcode: 2001AJ....122.3466M, doi: 10.1086/323920, retrieved 2015-07-22