Psi Octantis
  | |
| Observation data Epoch J2000.0 Equinox J2000.0 (ICRS) | |
|---|---|
| Constellation | Octans |
| Right ascension | 22h 17m 50.5954s[1] |
| Declination | −77° 30′ 41.599″[1] |
| Apparent magnitude (V) | 5.47±0.01[2] |
| Characteristics | |
| Evolutionary stage | main sequence[1] |
| Spectral type | F0IIp[3] (F4V:kA5)[4] |
| U−B color index | +0.12[5] |
| B−V color index | +0.31[5] |
| Astrometry | |
| Radial velocity (Rv) | 17.0±1.6[6] km/s |
| Proper motion (μ) | RA: −37.392 mas/yr[1] Dec.: +13.788 mas/yr[1] |
| Parallax (π) | 25.7575 ± 0.0505 mas[1] |
| Distance | 126.6 ± 0.2 ly (38.82 ± 0.08 pc) |
| Absolute magnitude (MV) | +2.56[7] |
| Details | |
| Mass | 1.49±0.07[8] M☉ |
| Radius | 1.74±0.04[8] R☉ |
| Luminosity | 7.82[7] L☉ |
| Surface gravity (log g) | 4.13±0.05[8] cgs |
| Temperature | 7,244[8] K |
| Metallicity [Fe/H] | −0.04[9] dex |
| Age | 1.41[9] Gyr |
| Other designations | |
| Database references | |
| SIMBAD | data |
Psi Octantis, Latinized from ψ Octantis, is a solitary[12] star in the southern circumpolar constellation Octans. It has an apparent magnitude of 5.47,[2] allowing it to be seen with the naked eye under ideal conditions. The star is relatively close at a distance of 126 light years[1] but is receding with a heliocentric radial velocity of 17 km/s.[6]
Psi Octantis has a spectral classification of F0IIp, suggesting that it is a bright giant but with peculiarities. Other assessments give a luminosity class of III (giant),[13] III-IV (intermediate between giant and subgiant),[14] or V: (approximately main sequence).[4] One paper gives a spectral class of F4V:kA5, indicating that it is a probable F-type main-sequence star with the calcium K-lines of an A5 star, including sharp absorption lines of metals.[4] Analysis of its evolutionary stage show it to be a somewhat evolved main sequence star.[1]
It has 149% the mass of the Sun and 1.74 times the radius of the Sun.[8] It shines at 7.82 times the luminosity of the Sun[7] from its photosphere at an effective temperature of 7,244 K,[8] giving it a yellowish white glow. Psi Octantis has an iron abundance 91% that of the Sun and is estimated to be 1.41 billion years old.[9]
References
[edit]- ^ a b c d e f g Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 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.
- ^ Gray, R. O.; Corbally, C. J.; Garrison, R. F.; McFadden, M. T.; Bubar, E. J.; McGahee, C. E.; O'Donoghue, A. A.; Knox, E. R. (2 June 2006). "Contributions to the Nearby Stars (NStars) Project: Spectroscopy of Stars Earlier than M0 within 40 pc--The Southern Sample". The Astronomical Journal. 132 (1): 161–170. arXiv:astro-ph/0603770. Bibcode:2006AJ....132..161G. doi:10.1086/504637. eISSN 1538-3881. ISSN 0004-6256.
- ^ a b c Hoffleit, Dorrit (1953). "The spectra and absolute magnitudes of 500 A3 - G2 stars". Annals of Harvard College Observatory. 0119: 1–35. Bibcode:1953AnHar.119....1H.
- ^ a b Johnson, H. L.; Mitchell, R. I.; Iriarte, B.; Wisniewski, W. Z. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99–110. Bibcode:1966CoLPL...4...99J.
- ^ a b Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35 495 Hipparcos stars in a common system". Astronomy Letters. 32 (11): 759–771. arXiv:1606.08053. Bibcode:2006AstL...32..759G. doi:10.1134/S1063773706110065. eISSN 1562-6873. ISSN 1063-7737. S2CID 119231169.
- ^ a b c Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation". Astronomy Letters. 38 (5): 331–346. arXiv:1108.4971. Bibcode:2012AstL...38..331A. doi:10.1134/S1063773712050015. ISSN 1063-7737. S2CID 119257644.
- ^ a b c d e f Allende Prieto, C.; Lambert, D. L. (December 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. ISSN 0004-6361.
- ^ a b c Gontcharov, G. A. (December 2012). "Dependence of kinematics on the age of stars in the solar neighborhood". Astronomy Letters. 38 (12): 771–782. arXiv:1606.08814. Bibcode:2012AstL...38..771G. doi:10.1134/S1063773712120031. ISSN 0320-0108. S2CID 118345778.
- ^ Gould, Benjamin Apthorp (1878). "Uranometria Argentina : brillantez y posicion de las estrellas fijas, hasta la septima magnitud, comprendidas dentro de cien grados del polo austral : con atlas". Resultados del Observatorio Nacional Argentino. 1. Bibcode:1879RNAO....1.....G.
- ^ "Psi oct". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved May 20, 2022.
- ^ 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.
- ^ Houk, N.; Cowley, A. P. (1975). University of Michigan Catalogue of two-dimensional spectral types for the HD stars. Volume I. Declinations −90° to −53°. Bibcode:1975mcts.book.....H.
- ^ Abt, Helmut A.; Morrell, Nidia I. (July 1995). "The Relation between Rotational Velocities and Spectral Peculiarities among A-Type Stars". The Astrophysical Journal Supplement Series. 99: 135. Bibcode:1995ApJS...99..135A. doi:10.1086/192182. ISSN 0067-0049.
