Astronomy:Delta2 Gruis
From HandWiki
Short description: Variable star in the constellation Grus
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Grus |
| Right ascension | 22h 29m 45.43402s[2] |
| Declination | −43° 44′ 57.1968″[2] |
| Apparent magnitude (V) | 3.99 - 4.20[3] |
| Characteristics | |
| Spectral type | M4.5 IIIa[4] |
| U−B color index | +1.71[5] |
| B−V color index | +1.57[5] |
| Variable type | LB?[3] |
| Astrometry | |
| Radial velocity (Rv) | +2.7±0.8[6] km/s |
| Proper motion (μ) | RA: −14.08[2] mas/yr Dec.: +2.57[2] mas/yr |
| Parallax (π) | 9.1556 ± 0.1885[7] mas |
| Distance | 356 ± 7 ly (109 ± 2 pc) |
| Absolute magnitude (MV) | −0.90±0.05[4] |
| Details | |
| Radius | 97[8] R☉ |
| Luminosity | 1,359[8] L☉ |
| Surface gravity (log g) | +0.45[8] cgs |
| Temperature | 3,560[8] K |
| Rotational velocity (v sin i) | +4.5±0.8[9] km/s |
| Other designations | |
| Database references | |
| SIMBAD | data |
Delta2 Gruis, Latinized from δ2 Gruis, is a solitary,[11] red-hued star in the southern constellation of Grus. It is visible to the naked eye with an apparent visual magnitude of about 4. Based upon an annual parallax shift of 9.88 mas as seen from the Earth, the star is located around 330 light years from the Sun. It is moving further away from the Sun with a radial velocity of +3 km/s.[6]
This is an evolved red giant star with a stellar classification of M4.5 IIIa.[4] It is a pulsating variable with multiple periods, including 20.6, 24.1, 24.5, and 32.3 days. The strongest period is 33.3 days with an amplitude of 0.043 magnitude.[12] It has a magnitude 9.71 visual companion at an angular separation of 60.4 arc seconds along a position angle of 210°, as of 2013.[13]
References
- ↑ "/ftp/cats/more/HIP/cdroms/cats". Strasbourg astronomical Data Center. https://cdsarc.cds.unistra.fr/viz-bin/ftp-index?/ftp/cats/more/HIP/cdroms/cats.
- ↑ 2.0 2.1 2.2 2.3 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V.
- ↑ 3.0 3.1 Samus, N. N. et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S 1: B/gcvs. Bibcode: 2009yCat....102025S.
- ↑ 4.0 4.1 4.2 Park, Sunkyung et al. (2013), "Wilson-Bappu Effect: Extended to Surface Gravity", The Astronomical Journal 146 (4): 73, doi:10.1088/0004-6256/146/4/73, Bibcode: 2013AJ....146...73P.
- ↑ 5.0 5.1 Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series 34: 1–49, Bibcode: 1978A&AS...34....1N.
- ↑ 6.0 6.1 Gontcharov, G. A. (November 2006), "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system", Astronomy Letters 32 (11): 759–771, doi:10.1134/S1063773706110065, Bibcode: 2006AstL...32..759G.
- ↑ Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode: 2021A&A...649A...1G. Gaia EDR3 record for this source at VizieR.
- ↑ 8.0 8.1 8.2 8.3 McDonald, I.; Zijlstra, A. A.; Watson, R. A. (2017). "Fundamental parameters and infrared excesses of Tycho-Gaia stars". Monthly Notices of the Royal Astronomical Society 471 (1): 770. doi:10.1093/mnras/stx1433. Bibcode: 2017MNRAS.471..770M.
- ↑ Zamanov, R. K. et al. (October 2008), "Rotational velocities of the giants in symbiotic stars - III. Evidence of fast rotation in S-type symbiotics", Monthly Notices of the Royal Astronomical Society 390 (1): 377–382, doi:10.1111/j.1365-2966.2008.13751.x, Bibcode: 2008MNRAS.390..377Z.
- ↑ "del02 Gru". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=del02+Gru.
- ↑ 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, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.
- ↑ "Long-term photometry and periods for 261 nearby pulsating M giants", Monthly Notices of the Royal Astronomical Society 400 (4): 1945–61, 2009, doi:10.1111/j.1365-2966.2009.15588.x, Bibcode: 2009MNRAS.400.1945T.
- ↑ Mason, B. D. et al. (2014), "The Washington Visual Double Star Catalog", The Astronomical Journal 122 (6): 3466–3471, doi:10.1086/323920, Bibcode: 2001AJ....122.3466M, http://vizier.u-strasbg.fr/viz-bin/VizieR?-source=B/wds, retrieved 2015-07-22
 |  |
