HD 166006
Double star in the constellation Telescopium
HD 166006 , also known as HR 6778 , is a solitary orange-hued star located in the southern constellation Telescopium . It has an apparent magnitude of 6.07, making it barely visible to the naked eye . Based on Gaia DR2 parallax measurements, the object is located 582 light years away. It is currently approaching the Solar System with a somewhat constrained heliocentric radial velocity of −15 km/s .
HD 166006 has a stellar classification of K1 III CN2,[ 3] which indicates that it is an evolved red giant with a strong overabundance of cyano radicals in its spectrum, making it a CN star . At the estimated distance of HD 166006, the star has an angular diameter of 1.05 mas .[ 10] This yields a radius of 20.1 R ☉ .[ 9] It has 1.24 times the mass of the Sun [ 8] and radiates 165 times the luminosity of the Sun [ 7] from its enlarged photosphere at an effective temperature of 4,529 K .[ 10] The star is slightly metal deficient ([Fe/H] = −0.07[ 8] ) and spins a little too slowly to be accurately measured.[ 11] HD 166006 has an optical 11th magnitude companion located 1.8" away along a position angle of 271° as of 2015.[ 13]
References
^ a b c 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 .
^ 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 .
^ a b Houk, Nancy (1978). Michigan catalogue of two-dimensional spectral types for the HD stars Volume II: Declinations −53° to −40° . Bibcode :1978mcts.book.....H .
^ 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 .
^ 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 .
^ van Leeuwen, Floor (13 August 2007). "Validation of the new Hipparcos reduction" . Astronomy & Astrophysics . 474 (2): 653–664. arXiv :0708.1752 . Bibcode :2007A&A...474..653V . doi :10.1051/0004-6361:20078357 . eISSN 1432-0746 . ISSN 0004-6361 . Hipparcos record for this source at VizieR .
^ a b c Anderson, E.; Francis, Ch. (1 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 Anders, F.; et al. (1 August 2019). "Photo-astrometric distances, extinctions, and astrophysical parameters for Gaia DR2 stars brighter than G = 18" (PDF) . Astronomy and Astrophysics . 628 : A94. arXiv :1904.11302 . Bibcode :2019A&A...628A..94A . doi :10.1051/0004-6361/201935765 . ISSN 0004-6361 . S2CID 131780028 .
^ a b Lang, Kenneth R. (2006), Astrophysical formulae , Astronomy and astrophysics library, vol. 1 (3 ed.), Birkhäuser , ISBN 3-540-29692-1 . The radius (R* ) is given by:
2
⋅ ⋅ -->
R
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=
(
178
⋅ ⋅ -->
1.05
⋅ ⋅ -->
10
− − -->
3
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AU
0.0046491
AU
/
R
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≈ ≈ -->
40.2
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R
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{\displaystyle {\begin{aligned}2\cdot R_{*}&={\frac {(178\cdot 1.05\cdot 10^{-3})\ {\text{AU}}}{0.0046491\ {\text{AU}}/R_{\bigodot }}}\\&\approx 40.2\cdot R_{\bigodot }\end{aligned}}}
^ a b c Stevens, Daniel J.; Stassun, Keivan G.; Gaudi, B. Scott (1 December 2017). "Empirical Bolometric Fluxes and Angular Diameters of 1.6 Million Tycho-2 Stars and Radii of 350,000 Stars with Gaia DR1 Parallaxes" . The Astronomical Journal . 154 (6): 259. arXiv :1708.05025 . Bibcode :2017AJ....154..259S . doi :10.3847/1538-3881/aa957b . ISSN 0004-6256 . S2CID 119191064 .
^ a b De Medeiros, J. R.; Alves, S.; Udry, S.; Andersen, J.; Nordström, B.; Mayor, M. (1 January 2014). "A catalog of rotational and radial velocities for evolved stars. V. Southern stars". Astronomy and Astrophysics . 561 : A126. arXiv :1312.3474 . Bibcode :2014A&A...561A.126D . doi :10.1051/0004-6361/201220762 . ISSN 0004-6361 . S2CID 54046583 .
^ "HR 6778" . SIMBAD . Centre de données astronomiques de Strasbourg . Retrieved 15 September 2021 .
^ Mason, Brian D.; Wycoff, Gary L.; Hartkopf, William I.; Douglass, Geoffrey G.; Worley, Charles E. (1 December 2001). "The 2001 US Naval Observatory Double Star CD-ROM. I. The Washington Double Star Catalog" . The Astronomical Journal . 122 (6): 3466–3471. Bibcode :2001AJ....122.3466M . doi :10.1086/323920 . ISSN 0004-6256 .