Community hub
0 subscribers8 pages, 0 posts
Recent from talks
All channels
Be the first to start a discussion here.
Be the first to start a discussion here.
Be the first to start a discussion here.
Be the first to start a discussion here.
Contribute something
Welcome to the community hub built to collect knowledge and have discussions related to Theta Octantis.
Nothing was collected or created yet.
Theta Octantis
View on Wikipediafrom Wikipedia
  | |
| Observation data Epoch J2000 Equinox J2000 | |
|---|---|
| Constellation | Octans[1] |
| Right ascension | 00h 01m 35.70158s[2] |
| Declination | −77° 03′ 56.6092″[2] |
| Apparent magnitude (V) | 4.78[1] |
| Characteristics | |
| Evolutionary stage | red clump[3] |
| Spectral type | K3III[4] |
| U−B color index | +1.41[5] |
| B−V color index | +1.27[5] |
| Astrometry | |
| Radial velocity (Rv) | +22.48±0.17[6] km/s |
| Proper motion (μ) | RA: −57.30[2] mas/yr Dec.: −177.06[2] mas/yr |
| Parallax (π) | 15.02±0.18 mas[2] |
| Distance | 217 ± 3 ly (66.6 ± 0.8 pc) |
| Absolute magnitude (MV) | 0.66[1] |
| Details | |
| Mass | 1.20[7] M☉ |
| Radius | 15.84+0.42 −1.02[6] R☉ |
| Luminosity | 79.2±1.5[6] L☉ |
| Surface gravity (log g) | 2.16[7] cgs |
| Temperature | 4,325+147 −55[6] K |
| Rotational velocity (v sin i) | < 1.0[8] km/s |
| Other designations | |
| θ Oct, CPD−77°1596, FK5 904, GC 33321, HD 224889, HIP 122, HR 9084, SAO 258207[9] | |
| Database references | |
| SIMBAD | data |
θ Octantis, Latinized as Theta Octantis, is a single[10] star in the southern circumpolar constellation of Octans, near the constellation border with Hydrus. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 4.78.[1] The star is located approximately 217 light years from the Sun based on parallax,[2] and is drifting further away with a radial velocity of +22.5 km/s.[6]
This is an aging giant star with a stellar classification of K3III,[4] having exhausted the supply of hydrogen at its core then cooled and expanded. It has been catalogued as a red clump giant,[3] which would indicate it is on the horizontal branch and is undergoing core helium fusion. At present it has 16[6] times the radius of the Sun. This star has 1.20[7] times the mass of the Sun and is radiating 79[6] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,325 K.[6]
References
[edit]- ^ a b c d 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. Vizier catalog entry
- ^ a b c d e f 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 Gontcharov, G. A. (2009). "Red giant clump in the Tycho-2 catalogue". Astronomy Letters. 34 (11): 785–796. arXiv:1607.00619. Bibcode:2008AstL...34..785G. doi:10.1134/S1063773708110078. S2CID 73524157. Vizier catalog entry
- ^ a b Houk, Nancy; Cowley, A. P. (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. Vol. 1. Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan. Bibcode:1978mcts.book.....H.
- ^ a b Mallama, A. (2014). "Sloan Magnitudes for the Brightest Stars". The Journal of the American Association of Variable Star Observers. 42 (2): 443. Bibcode:2014JAVSO..42..443M. Vizier catalog entry
- ^ a b c d e f g h 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 Allende Prieto, C.; Lambert, D. L. (1999). "Fundamental parameters of nearby stars from the comparison with evolutionary calculations: Masses, radii and effective temperatures". Astronomy and Astrophysics. 352: 555–562. arXiv:astro-ph/9911002. Bibcode:1999A&A...352..555A. Vizier catalog entry
- ^ De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (2014). "A catalog of rotational and radial velocities for evolved stars". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. S2CID 54046583. Vizier catalog entry
- ^ "tet Oct". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-08-30.
{{cite web}}: CS1 maint: postscript (link) - ^ 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.
