Pi1 Octantis

π1 Octantis
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Octans
Right ascension 15h 01m 50.7983s[1]
Declination −83° 13′ 39.5303″[1]
Apparent magnitude (V) 5.64±0.01[2]
Characteristics
Spectral type G8/K0 III[3]
U−B color index +0.74[4]
B−V color index +0.95[4]
Astrometry
Radial velocity (Rv)13.6±0.4[5] km/s
Proper motion (μ) RA: +18.954 mas/yr[1]
Dec.: +52.520 mas/yr[1]
Parallax (π)8.419 ± 0.0349 mas[1]
Distance387 ± 2 ly
(118.8 ± 0.5 pc)
Absolute magnitude (MV)+0.24[6]
Details[7]
Mass2.74±0.15 M
Radius11.62±0.21 R
Luminosity76.2±1.7 L
Surface gravity (log g)2.7±0.1 cgs
Temperature5,002±36 K
Metallicity [Fe/H]−0.01±0.03 dex
Rotational velocity (v sin i)<1[8] km/s
Other designations
π1 Oct, 21 G. Octantis, CPD−82°629, FK5 3987, GC 20070, HD 130650, HIP 73540, HR 5525, SAO 258713[9][10]
Database references
SIMBADdata

Pi1 Octantis (Pi1 Oct), Latinized π1 Octantis, is a solitary[11] star in the southern circumpolar constellation Octans. It is faintly visible to the naked eye with an apparent magnitude 5.64, and is estimated to be 387 light years away. However, it is receding with a heliocentric radial velocity of 14 km/s.[5]

Pi1 Oct has a stellar classification of G8/K0 III[3] — intermediate between a G8 and K0 giant star. It has 2.74 times the mass of the Sun and an effective temperature of 5,002 k,[7] giving a yellow hue. However, an enlarged radius of 11.62 R yields a luminosity 76 times that of the Sun.[7] Pi1 Oct has a metallicity[7] around solar level and spins with a projected rotational velocity lower than km/s.[8]

References

[edit]
  1. ^ a b c d Brown, A. G. A.; et al. (Gaia collaboration) (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics. 649: A1. arXiv:2012.01533. Bibcode:2021A&A...649A...1G. doi:10.1051/0004-6361/202039657. S2CID 227254300. (Erratum: doi:10.1051/0004-6361/202039657e). Gaia EDR3 record for this source at VizieR.
  2. ^ 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.
  3. ^ a b 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_ƒ0. Bibcode:1975mcts.book.....H.
  4. ^ 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.
  5. ^ 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. ISSN 1063-7737. S2CID 119231169.
  6. ^ 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 255204555.
  7. ^ a b c d Ottoni, G.; Udry, S.; Ségransan, D.; Buldgen, G.; Lovis, C.; Eggenberger, P.; Pezzotti, C.; Adibekyan, V.; Marmier, M.; Mayor, M.; Santos, N. C.; Sousa, S. G.; Lagarde, N.; Charbonnel, C. (January 2022). "CORALIE radial-velocity search for companions around evolved stars (CASCADES): I. Sample definition and first results: Three new planets orbiting giant stars". Astronomy & Astrophysics. 657: A87. arXiv:2201.01528. Bibcode:2022A&A...657A..87O. doi:10.1051/0004-6361/202040078. ISSN 0004-6361.
  8. ^ a b De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (January 2014). "A catalog of rotational and radial velocities for evolved stars: V. Southern stars⋆⋆⋆". Astronomy & Astrophysics. 561: A126. arXiv:1312.3474. Bibcode:2014A&A...561A.126D. doi:10.1051/0004-6361/201220762. ISSN 0004-6361.
  9. ^ "HD 46568". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 7 June 2022.
  10. ^ 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.
  11. ^ Eggleton, P. P.; Tokovinin, A. A. (11 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. eISSN 1365-2966. ISSN 0035-8711.