Iota Tucanae
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Tucana |
| Right ascension | 01h 07m 18.66365s[1] |
| Declination | −61° 46′ 31.0434″[1] |
| Apparent magnitude (V) | +5.33[2] |
| Characteristics | |
| Spectral type | G5 III[3] |
| B−V color index | +0.89[2] |
| Variable type | SRV[4] |
| Astrometry | |
| Radial velocity (Rv) | −7.80[4] km/s |
| Proper motion (μ) | RA: +73.80[1] mas/yr Dec.: −11.55[1] mas/yr |
| Parallax (π) | 10.72 ± 0.23[1] mas |
| Distance | 304 ± 7 ly (93 ± 2 pc) |
| Absolute magnitude (MV) | 0.70[5] |
| Details | |
| Mass | 2.20[4] M☉ |
| Radius | 11[6] R☉ |
| Luminosity | 65[4] L☉ |
| Surface gravity (log g) | 3.15±0.13[7] cgs |
| Temperature | 5,039±63[4] K |
| Metallicity [Fe/H] | −0.02±0.08[7] dex |
| Rotational velocity (v sin i) | 5.8±3.5[5] km/s |
| Age | 1.69[4] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Iota Tucanae (ι Tuc, ι Tucanae) is a solitary[9] star in the southern constellation of Tucana. Based upon an annual parallax shift of 10.72 mas as seen from Earth,[1] it is located around 304 light years from the Sun. With an apparent visual magnitude of +5.33,[2] it is faintly visible to the naked eye.
This is a yellow-hued G-type giant star with a stellar classification of G5 III.[3] It is classified as a semiregular variable star, showing a periodicity of 66.8 days with an amplitude of 0.0202 in visual magnitude.[10] Iota Tucanae is an X-ray source with a luminosity of 817.6×1028 erg s−1.[11] It has an estimated 2.2[4] times the mass of the Sun, and, at the age of 1.69 billion years,[4] it has evolved away from the main sequence, expanding to 11[6] times the Sun's radius. The star radiates 65[4] times the solar luminosity from its photosphere at an effective temperature of 5,039 K.[4]
References
- 1 2 3 4 5 6 van Leeuwen, F. (2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, Bibcode:2007A&A...474..653V, arXiv:0708.1752
, doi:10.1051/0004-6361:20078357. - 1 2 3 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.
- 1 2 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.
- 1 2 3 4 5 6 7 8 9 10 Luck, R. Earle (September 2015), "Abundances in the Local Region. I. G and K Giants", The Astronomical Journal, 150 (3): 23, Bibcode:2015AJ....150...88L, arXiv:1507.01466 , doi:10.1088/0004-6256/150/3/88, 88.
- 1 2 Ammler-von Eiff, M.; Reiners, A. (June 2012), "New measurements of rotation and differential rotation in A-F stars: are there two populations of differentially rotating stars?", Astronomy & Astrophysics, 542: 31, Bibcode:2012A&A...542A.116A, arXiv:1204.2459 , doi:10.1051/0004-6361/201118724, A116.
- 1 2 Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy and Astrophysics (3rd ed.), 367: 521–524, Bibcode:2001A&A...367..521P, arXiv:astro-ph/0012289 , doi:10.1051/0004-6361:20000451.
- 1 2 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, Bibcode:2015MNRAS.448.2749A, arXiv:1503.02556 , doi:10.1093/mnras/stv189.
- ↑ "iot Tuc -- Long-period variable star", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, 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, Bibcode:2008MNRAS.389..869E, arXiv:0806.2878 , doi:10.1111/j.1365-2966.2008.13596.x.
- ↑ Koen, Chris; Eyer, Laurent (2002), "New periodic variables from the Hipparcos epoch photometry", Monthly Notices of the Royal Astronomical Society, 331: 45, Bibcode:2002MNRAS.331...45K, arXiv:astro-ph/0112194 , doi:10.1046/j.1365-8711.2002.05150.x.
- ↑ 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.