Astronomy:Pi1 Octantis

From HandWiki
Short description: Star in the constellation of Octans


π1 Octantis
Observation data
Epoch J2000.0   Equinox (celestial coordinates)
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[1] mas/yr
Dec.: +52.520[1] mas/yr
Parallax (π)8.419 ± 0.0349[1] mas
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, 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

  1. 1.0 1.1 1.2 1.3 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode2021A&A...649A...1G.  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. et al. (March 2000). "The Tycho-2 catalogue of the 2.5 million brightest stars". Astronomy and Astrophysics 355: L27–L30. ISSN 0004-6361. Bibcode2000A&A...355L..27H. 
  3. 3.0 3.1 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.. Bibcode1975mcts.book.....H. 
  4. 4.0 4.1 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. Bibcode1966CoLPL...4...99J. 
  5. 5.0 5.1 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. doi:10.1134/S1063773706110065. ISSN 1063-7737. Bibcode2006AstL...32..759G. 
  6. Anderson, E.; Francis, Ch. (May 2012). "XHIP: An extended hipparcos compilation" (in en). Astronomy Letters 38 (5): 331–346. doi:10.1134/S1063773712050015. ISSN 1063-7737. Bibcode2012AstL...38..331A. 
  7. 7.0 7.1 7.2 7.3 Ottoni, G.; Udry, S.; Ségransan, D.; Buldgen, G.; Lovis, C.; Eggenberger, P.; Pezzotti, C.; Adibekyan, V. et al. (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. doi:10.1051/0004-6361/202040078. ISSN 0004-6361. Bibcode2022A&A...657A..87O. 
  8. 8.0 8.1 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. doi:10.1051/0004-6361/201220762. ISSN 0004-6361. Bibcode2014A&A...561A.126D. 
  9. "HD 46568". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=HD+46568. 
  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. Bibcode1879RNAO....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. doi:10.1111/j.1365-2966.2008.13596.x. ISSN 0035-8711. Bibcode2008MNRAS.389..869E.