Astronomy:Iota Tucanae
| Observation data Equinox J2000.0]] (ICRS) | |
|---|---|
| Constellation | Tucana |
| Right ascension | 01h 07m 18.66365s[2] |
| Declination | −61° 46′ 31.0434″[2] |
| Apparent magnitude (V) | +5.33[3] |
| Characteristics | |
| Spectral type | G5 III[4] |
| B−V color index | +0.89[3] |
| Variable type | SRV[5] |
| Astrometry | |
| Radial velocity (Rv) | −7.80[5] km/s |
| Proper motion (μ) | RA: +73.80[2] mas/yr Dec.: −11.55[2] mas/yr |
| Parallax (π) | 10.72 ± 0.23[2] mas |
| Distance | 304 ± 7 ly (93 ± 2 pc) |
| Absolute magnitude (MV) | 0.70[6] |
| Details | |
| Mass | 2.20[5] M☉ |
| Radius | 11[7] R☉ |
| Luminosity | 65[5] L☉ |
| Surface gravity (log g) | 3.15±0.13[8] cgs |
| Temperature | 5,039±63[5] K |
| Metallicity [Fe/H] | −0.02±0.08[8] dex |
| Rotational velocity (v sin i) | 5.8±3.5[6] km/s |
| Age | 1.69[5] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Iota Tucanae (ι Tuc, ι Tucanae) is a solitary[10] star in the southern constellation of Tucana. Based upon an annual parallax shift of 10.72 mas as seen from Earth,[2] it is located around 304 light years from the Sun. With an apparent visual magnitude of +5.33,[3] it is faintly visible to the naked eye.
This is a yellow-hued G-type giant star with a stellar classification of G5 III.[4] It is classified as a semiregular variable star, showing a periodicity of 66.8 days with an amplitude of 0.0202 in visual magnitude.[11] Iota Tucanae is an X-ray source with a luminosity of 817.6×1028 erg s−1.[12] It has an estimated 2.2[5] times the mass of the Sun, and, at the age of 1.69 billion years,[5] it has evolved away from the main sequence, expanding to 11[7] times the Sun's radius. The star radiates 65[5] times the solar luminosity from its photosphere at an effective temperature of 5,039 K.[5]
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 2.4 2.5 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 3.2 Corben, P. M.; Stoy, R. H. (1968), "Photoelectric Magnitudes and Colours for Bright Southern Stars", Monthly Notes of the Astronomical Society of Southern Africa 27: 11, Bibcode: 1968MNSSA..27...11C.
- ↑ 4.0 4.1 Houk, Nancy (1979), Michigan catalogue of two-dimensional spectral types for the HD stars, 1, Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan, Bibcode: 1978mcts.book.....H.
- ↑ 5.0 5.1 5.2 5.3 5.4 5.5 5.6 5.7 5.8 5.9 Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal 150 (3): 23, doi:10.1088/0004-6256/150/3/88, 88, Bibcode: 2015AJ....150...88L.
- ↑ 6.0 6.1 Ammler-von Eiff, Matthias; Reiners, Ansgar (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics 542: A116, doi:10.1051/0004-6361/201118724, Bibcode: 2012A&A...542A.116A.
- ↑ 7.0 7.1 Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics 367: 521–524, doi:10.1051/0004-6361:20000451, Bibcode: 2001A&A...367..521P.
- ↑ 8.0 8.1 Alves, S. et al. (April 2015), "Determination of the spectroscopic stellar parameters for 257 field giant stars", Monthly Notices of the Royal Astronomical Society 448 (3): 2749–2765, doi:10.1093/mnras/stv189, Bibcode: 2015MNRAS.448.2749A.
- ↑ "iot Tuc -- Long-period variable star", SIMBAD Astronomical Database (Centre de Données astronomiques de Strasbourg), http://simbad.u-strasbg.fr/simbad/sim-id?Ident=iot+Tuc, retrieved 2017-04-22.
- ↑ 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.
- ↑ Koen, Chris; Eyer, Laurent (2002), "New periodic variables from the Hipparcos epoch photometry", Monthly Notices of the Royal Astronomical Society 331 (1): 45–59, doi:10.1046/j.1365-8711.2002.05150.x, Bibcode: 2002MNRAS.331...45K.
- ↑ Pizzolato, N. et al. (September 2000), "Evolution of X-ray activity of 1-3 Msun late-type stars in early post-main-sequence phases", Astronomy and Astrophysics 361: 614–628, Bibcode: 2000A&A...361..614P.
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