Astronomy:Theta Pavonis

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Short description: A-type main sequence star in the constellation Pavo
θ Pavonis
Pavo constellation map.svg
Red circle.svg
Location of θ Pavonis (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Pavo
Right ascension  18h 48m 37.90451s[1]
Declination −65° 04′ 39.6498″[1]
Apparent magnitude (V) 5.71[2]
Characteristics
Evolutionary stage main sequence
Spectral type A8V[3]
B−V color index +0.268±0.004[2]
Astrometry
Radial velocity (Rv)−0.7±4.3[4] km/s
Proper motion (μ) RA: −38.266[1] mas/yr
Dec.: −78.246[1] mas/yr
Parallax (π)15.3252 ± 0.0741[1] mas
Distance213 ± 1 ly
(65.3 ± 0.3 pc)
Absolute magnitude (MV)1.56[2]
Details
Mass1.56[5] M
Radius2.51+0.09
−0.13
[1] R
Luminosity17.4±0.1[1] L
Surface gravity (log g)3.94±0.14[5] cgs
Temperature7,453+199
−136
[1] K
Metallicity [Fe/H]+0.01[6] dex
Rotational velocity (v sin i)245[7] km/s
Age425[5] Myr
Other designations
θ Oct, CPD−65°3754, GC 25706, HD 173168, HIP 92294, HR 7036, SAO 254374[8]
Database references
SIMBADdata

θ Pavonis, Latinized as Theta Pavonis, is a single[9] star in the southern constellation of Pavo. It is just visible to the naked eye as a dim, white-hued star, having an apparent visual magnitude of 5.71.[2] This star is located 213 light years from the Sun based on parallax.[1]

This object is an A-type main-sequence star with a stellar classification of A8V,[3] which indicates it is generating energy through hydrogen fusion at its core. It displays little to no detectable X-ray emission, suggesting a weak corona[10] and, at best, a shallow convection zone.[11] Theta Pavonis is 425[5] million years old and is spinning rapidly with a projected rotational velocity of 245 km/s.[7] The star has 1.56[5] times the mass of the Sun and 2.51[1] times the Sun's radius. It is radiating 17.4[1] times the luminosity of the Sun from its photosphere at an effective temperature of 7,453 K.[1]

It lies six arc-minutes north of the barred lenticular galaxy NGC 6684.[citation needed]

References

  1. 1.00 1.01 1.02 1.03 1.04 1.05 1.06 1.07 1.08 1.09 1.10 1.11 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A. 
  3. 3.0 3.1 Houk, Nancy; Cowley, A. P. (1979). Michigan catalogue of two-dimensional spectral types for the HD stars. 1. Ann Arbor, Michigan: Dept. of Astronomy, University of Michigan. Bibcode1978mcts.book.....H. 
  4. Gontcharov, G. A. (November 2006). "Pulkovo Compilation of Radial Velocities for 35495 Hipparcos stars in a common system". Astronomy Letters 32 (11): 759–771. doi:10.1134/S1063773706110065. Bibcode2006AstL...32..759G. 
  5. 5.0 5.1 5.2 5.3 5.4 David, Trevor J.; Hillenbrand, Lynne A. (2015). "The Ages of Early-Type Stars: Strömgren Photometric Methods Calibrated, Validated, Tested, and Applied to Hosts and Prospective Hosts of Directly Imaged Exoplanets". The Astrophysical Journal 804 (2): 146. doi:10.1088/0004-637X/804/2/146. Bibcode2015ApJ...804..146D. 
  6. Netopil, Martin (August 2017). "Metallicity calibrations for dwarf stars and giants in the Geneva photometric system". Monthly Notices of the Royal Astronomical Society 469 (3): 3042–3055. doi:10.1093/mnras/stx1077. Bibcode2017MNRAS.469.3042N. 
  7. 7.0 7.1 Glebocki, R.; Gnacinski, P. (2005). "Catalog of Stellar Rotational Velocities". in Favata, F.; Hussain, G. A. J.; Battrick, B.. Proceedings of the 13th Cambridge Workshop on Cool Stars, Stellar Systems and the Sun, held 5-9 July, 2004 in Hamburg, Germany. European Space Agency. p. 571. Bibcode2005csss...13..571G.  Seq. 31136
  8. "tet Pav". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=tet+Pav. 
  9. 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. doi:10.1111/j.1365-2966.2008.13596.x. Bibcode2008MNRAS.389..869E. 
  10. Simon, Theodore; Drake, Stephen A. (October 1993). "The Coronae of Main-Sequence A Stars". Astronomical Journal 106: 1660. doi:10.1086/116755. Bibcode1993AJ....106.1660S. 
  11. Piters, A. J. M.; van Paradijs, J.; Schmitt, J. H. M. M. (February 1998). "X-ray/optical observations of stars with shallow convection zones (A8-G2 V)". Astronomy and Astrophysics Supplement 128: 29–33. doi:10.1051/aas:1998126. Bibcode1998A&AS..128...29P.