Sigma1 Gruis, a Latinization of σ1 Gruis, is a star in the constellation Grus. It is a dim, white-hued star near the lower limit for visibility to the naked eye with an apparent visual magnitude of 6.26.[2] This object is located 229 light-years (70.1 pc) distant from the Sun based on parallax.[1] The radial velocity of this star is poorly constrained, but it appears to be drifting further away at the rate of +7 km/s.[3]
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Grus |
| Right ascension | 22h 36m 29.30230s[1] |
| Declination | −40° 34′ 57.7391″[1] |
| Apparent magnitude (V) | 6.26[2] |
| Characteristics | |
| Spectral type | A3 Vn[2] |
| B−V color index | +0.12[2] |
| Astrometry | |
| Radial velocity (Rv) | +6.9±3.4[3] km/s |
| Proper motion (μ) | RA: +46.00[4] mas/yr Dec.: −72.64[4] mas/yr |
| Parallax (π) | 14.2651 ± 0.0751 mas[1] |
| Distance | 229 ± 1 ly (70.1 ± 0.4 pc) |
| Absolute magnitude (MV) | +2.11[5] |
| Details[6] | |
| Mass | 2.00 M☉ |
| Radius | 2.0[7] R☉ |
| Luminosity | 12[5] L☉ |
| Surface gravity (log g) | 4.24±0.14 cgs |
| Temperature | 9,230±314 K |
| Rotational velocity (v sin i) | 163.4±2.0[8] km/s |
| Age | 194 Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
This is an A-type main-sequence star with a stellar classification of A2 Vn; a star that is currently fusing its core hydrogen. It has a relatively high rate of spin as indicated by the 'n' suffix, showing a projected rotational velocity of 163 km/s.[8] This object is 194 million years old with double the mass[6] and radius of the Sun.[7] The star is radiating 12[5] times the luminosity of the Sun from its photosphere at an effective temperature of 9,230 K.[6] It is a source of X-ray emission, which may indicate it has an unseen stellar companion.[10]
References
edit- ^ a b c d 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 Evans, D. S. (1966), "Fundamental data for Southern stars (6th list)", Royal Observatory Bulletin, 110: 185, Bibcode:1966RGOB..110..185E.
- ^ a b Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 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 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.
- ^ a b c 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 David, Trevor J.; Hillenbrand, Lynne A. (2015), "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets", The Astrophysical Journal, 804 (2): 146, arXiv:1501.03154, Bibcode:2015ApJ...804..146D, doi:10.1088/0004-637X/804/2/146, S2CID 33401607.
- ^ a b Pasinetti Fracassini, L. E.; et al. (2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy & Astrophysics, 367 (3rd ed.): 521–24, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
- ^ a b Díaz, C. G.; et al. (July 2011), "Accurate stellar rotational velocities using the Fourier transform of the cross correlation maximum", Astronomy & Astrophysics, 531: A143, arXiv:1012.4858, Bibcode:2011A&A...531A.143D, doi:10.1051/0004-6361/201016386, S2CID 119286673.
- ^ "sig01 Gru". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-24.
{{cite web}}: CS1 maint: postscript (link) - ^ Schröder, C.; Schmitt, J. H. M. M. (November 2007), "X-ray emission from A-type stars", Astronomy and Astrophysics, 475 (2): 677–684, Bibcode:2007A&A...475..677S, doi:10.1051/0004-6361:20077429.