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HD 139664

ACS image of debris disk around HD 139664
Credit: NASA/ESA
Observation data
Epoch J2000.0       Equinox J2000.0 ( ICRS)
Constellation Lupus
Right ascension 15h 41m 11.3774s [1]
Declination −44° 39′ 40.338″ [1]
Apparent magnitude (V) 4.64 [2]
Characteristics
Spectral type F3/5V [3]
U−B color index −0.03 [4]
B−V color index +0.413 [2]
R−I color index +0.20 [4]
Astrometry
Radial velocity (Rv)−7.08±0.03 [2] km/s
Proper motion (μ) RA: −168.70 [1]  mas/ yr
Dec.: −265.69 [1]  mas/ yr
Parallax (π)57.09 ± 0.72  mas [1]
Distance57.1 ± 0.7  ly
(17.5 ± 0.2  pc)
Absolute magnitude (MV)3.57 [5]
Details [6]
Mass1.368±0.026 [2]  M
Radius1.26 [7]  R
Luminosity3.31  L
Surface gravity (log g)4.29  cgs
Temperature6,704±63  K
Rotational velocity (v sin i)71.6 [2] km/s
Age1.11±1.40  Gyr
Other designations
g Lupi, CD−44° 10310, CPD−44° 7529, GC 21070, GJ 594, HD 139664, HIP 76829, HR 5825, SAO 226064, PPM 320883, LTT 6256, NLTT 40843 [8]
Database references
SIMBAD data

HD 139664 is a single [9] star in the southern constellation of Lupus. It has the Bayer designation g Lupi; HD 139664 is the star's identifier from the Henry Draper Catalogue. [8] It has a yellow-white hue and is visible to the naked eye with an apparent visual magnitude of 4.64. The star is located at a distance of 57  light years from the Sun based on parallax, [1] and it is drifting closer with a radial velocity of −7 km/s. [2] It is a member of the Hercules-Lyra Association of co-moving stars. [10] [2]

This is an F-type main-sequence star with a stellar classification of F3/5V, [3] which indicates it is generating energy through core hydrogen fusion. The estimated age is poorly constrained at around one billion years, [6] but the age of the Hercules-Lyra Association to which it belongs is 257±46 million years. [11] It has a moderately high rate of spin, showing a projected rotational velocity of 71.6 km/s. [2] The star has 1.37 [2] times the mass of the Sun and 1.26 [7] times the Sun's radius. It is radiating 3.31 times the luminosity of the Sun from its photosphere at an effective temperature of 6,704 K. [6]

Debris disk

A debris disk has been imaged around this star using the coronagraphic mode of the ACS instrument on the Hubble Space Telescope. The disk appears to have a dust maximum at 83 AU from the star and a sharp outer boundary at 109 AU. These features may be caused by gravitational perturbations from planets orbiting the star. [12]

References

  1. ^ a b c d e f van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics, 474 (2): 653–664, arXiv: 0708.1752, Bibcode: 2007A&A...474..653V, doi: 10.1051/0004-6361:20078357, S2CID  18759600.
  2. ^ a b c d e f g h i Desidera, S.; et al. (January 2015), "The VLT/NaCo large program to probe the occurrence of exoplanets and brown dwarfs in wide orbits. I. Sample definition and characterization", Astronomy & Astrophysics, 573: 45, arXiv: 1405.1559, Bibcode: 2015A&A...573A.126D, doi: 10.1051/0004-6361/201323168, S2CID  55486025, A126.
  3. ^ a b Houk, Nancy (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 2, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode: 1978mcts.book.....H.
  4. ^ a b Hoffleit, D.; Warren, W. H. Jr., "HR 5825, database entry", The Bright Star Catalogue (5th Revised ed.), retrieved February 4, 2011
  5. ^ Reiners, Ansgar (January 2006), "Rotation- and temperature-dependence of stellar latitudinal differential rotation", Astronomy and Astrophysics, 446 (1): 267–277, arXiv: astro-ph/0509399, Bibcode: 2006A&A...446..267R, doi: 10.1051/0004-6361:20053911, S2CID  8642707
  6. ^ a b c Luck, R. Earle (March 2018), "Abundances in the Local Region. III. Southern F, G, and K Dwarfs", The Astronomical Journal, 155 (3): 31, Bibcode: 2018AJ....155..111L, doi: 10.3847/1538-3881/aaa9b5, S2CID  125765376, 111.
  7. ^ a b Rhee, Joseph H.; et al. (May 2007), "Characterization of Dusty Debris Disks: The IRAS and Hipparcos Catalogs", The Astrophysical Journal, 660 (2): 1556–1571, arXiv: astro-ph/0609555, Bibcode: 2007ApJ...660.1556R, doi: 10.1086/509912, S2CID  11879505.
  8. ^ a b "g Lup". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2020-07-01.
  9. ^ Halbwachs, J. -L; et al. (2018), "Multiplicity among solar-type stars. IV. The CORAVEL radial velocities and the spectroscopic orbits of nearby K dwarfs", Astronomy and Astrophysics, 619: A81, arXiv: 1808.04605, Bibcode: 2018A&A...619A..81H, doi: 10.1051/0004-6361/201833377, S2CID  119437322.
  10. ^ Lopez-Santiago, J.; et al. (2006), "The Nearest Young Moving Groups", The Astrophysical Journal, 643 (2): 1160–1165, arXiv: astro-ph/0601573, Bibcode: 2006ApJ...643.1160L, doi: 10.1086/503183, S2CID  119520529.
  11. ^ Eisenbeiss, T.; et al. (August 2013), "The Hercules-Lyra association revisited. New age estimation and multiplicity study", Astronomy & Astrophysics, 556: 19, arXiv: 1312.4045, Bibcode: 2013A&A...556A..53E, doi: 10.1051/0004-6361/201118362, S2CID  119275785, A53.
  12. ^ Kalas, Paul; et al. (January 2006), "First Scattered Light Images of Debris Disks around HD 53143 and HD 139664", The Astrophysical Journal, 637 (1): L57–L60, arXiv: astro-ph/0601488, Bibcode: 2006ApJ...637L..57K, doi: 10.1086/500305, S2CID  18293244.