7 Trianguli
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Triangulum |
| Right ascension | 02h 15m 56.2876s[1] |
| Declination | +33° 21′ 32.032″[1] |
| Apparent magnitude (V) | 5.25±0.01[2] |
| Characteristics | |
| Spectral type | A0 V[3] or B9.5 V[4] |
| U−B color index | −0.03[5] |
| B−V color index | −0.01[5] |
| Astrometry | |
| Radial velocity (Rv) | −1.3±2[6] km/s |
| Proper motion (μ) | RA: −15.234[1] mas/yr Dec.: −32.711[1] mas/yr |
| Parallax (π) | 9.0683 ± 0.137 mas[1] |
| Distance | 360 ± 5 ly (110 ± 2 pc) |
| Absolute magnitude (MV) | 0.58[7] |
| Details | |
| Mass | 2.77[8] M☉ |
| Radius | 3.24±0.11[9] R☉ |
| Luminosity | 89.1+10.5 −8.1[9] L☉ |
| Surface gravity (log g) | 4.02±0.14[8] cgs |
| Temperature | 10685±363[8] K |
| Rotational velocity (v sin i) | 130[10] km/s |
| Age | 283[8] Myr |
| Other designations | |
| Database references | |
| SIMBAD | data |
7 Trianguli is a solitary[11] star located in the northern constellation Triangulum. It has an apparent magnitude of 5.25,[2] making it faintly visible to the naked eye under ideal conditions. The star is situated at distance of 360 light years[1] but is approaching with a heliocentric radial velocity of −1.3 km/s,[6] which is poorly constrained.
7 Trianguli has a stellar classification of A0 V[3] or B9.5 V,[4] depending on the study. At present it has 2.77 times the mass of the Sun[8] and 3.24 times the radius of the Sun.[9] It shines at 89.1 times the luminosity of the Sun[9] from its photosphere at an effective temperature of 10,685 K,[8] giving it a blueish white glow. 7 Trianguli is a young star, with an age of 283 million years[8] and spins rapidly with a projected rotational velocity of 130 km/s.[10] It has been classified as having a peculiar spectrum,[12] but it is considered doubtful that it is actually a chemically peculiar star.[13]
Together with δ Trianguli and γ Trianguli, it forms an optical (line-of-sight) triple.
References
[edit]- ^ a b c d e f Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
- ^ a b Høg, E.; Fabricius, C.; Makarov, V. V.; Urban, S.; Corbin, T.; Wycoff, G.; Bastian, U.; Schwekendiek, P.; Wicenec, A. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics. 355: L27–L30. Bibcode:2000A&A...355L..27H. ISSN 0004-6361.
- ^ a b Cowley, A.; Cowley, C.; Jaschek, M.; Jaschek, C. (April 1969). "A study of the bright stars. I. A catalogue of spectral classifications". The Astronomical Journal. 74: 375. Bibcode:1969AJ.....74..375C. doi:10.1086/110819. ISSN 0004-6256.
- ^ a b Eggen, O. J. (1962). "Space-velocity vectors for 3483 stars with proper motion and radial velocity". Royal Greenwich Observatory Bulletins. 51: 79. Bibcode:1962RGOB...51...79E.
- ^ a b Hamdy, M. A.; Abo Elazm, M. S.; Saad, S. M. (1993). "A catalogue of spectral classification and photometric data of B-type stars". Astrophysics and Space Science. 203 (1): 53–107. Bibcode:1993Ap&SS.203...53H. doi:10.1007/BF00659414. ISSN 0004-640X.
- ^ a b Wilson, Ralph Elmer (1953). "General catalogue of stellar radial velocities". Carnegie Institute Washington D.C. Publication: 0. Bibcode:1953GCRV..C......0W.
- ^ 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 d e f g David, Trevor J.; Hillenbrand, Lynne A. (12 May 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. ISSN 0004-637X.
- ^ a b c d Stassun, Keivan G.; et al. (9 September 2019). "The Revised TESS Input Catalog and Candidate Target List". The Astronomical Journal. 158 (4): 138. arXiv:1905.10694. Bibcode:2019AJ....158..138S. doi:10.3847/1538-3881/ab3467. ISSN 0004-6256.
- ^ a b Glebocki, R.; Gnacinski, P.; Stawikowski, A. (December 2000). "Catalog of Projected Rotational Velocities". Acta Astronomica. 50: 509–515. Bibcode:2000AcA....50..509G. ISSN 0001-5237.
- ^ 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
- ^ Cucchiaro, A.; Jaschek, M.; Jaschek, C.; Macau-Hercot, D. (1980). "Spectral classification from the ultraviolet line features of S2/68 spectra". Astronomy and Astrophysics Supplement Series. 40: 207. Bibcode:1980A&AS...40..207C.
- ^ Renson, P.; Manfroid, J. (May 2009). "Catalogue of Ap, HgMn and Am stars". Astronomy and Astrophysics. 498 (3): 961–966. Bibcode:2009A&A...498..961R. doi:10.1051/0004-6361/200810788.
