64 Aquilae, abbreviated 64 Aql, is a star in the equatorial constellation of Aquila. 64 Aquilae is its Flamsteed designation. It is a faint star that requires good viewing conditions to see, having an apparent visual magnitude of 5.97.[2] The distance to 64 Aql, as determined from its annual parallax shift of 21.42 mas,[1] is 152.2 light years. At that distance, the visual magnitude of the star is diminished by an extinction of 0.029 due to interstellar dust.[5] It is moving closer to the Earth with a heliocentric radial velocity of −3.6 km/s.[4]

64 Aquilae
Observation data
Epoch J2000      Equinox J2000
Constellation Aquila
Right ascension 20h 08m 01.82224s[1]
Declination −00° 40′ 41.4663″[1]
Apparent magnitude (V) 5.97[2]
Characteristics
Spectral type K1 III/IV[3]
B−V color index +1.023±0.003[2]
Astrometry
Radial velocity (Rv)−3.64±0.39[4] km/s
Proper motion (μ) RA: −115.520[1] mas/yr
Dec.: –67.593[1] mas/yr
Parallax (π)21.4233 ± 0.0627 mas[1]
Distance152.2 ± 0.4 ly
(46.7 ± 0.1 pc)
Absolute magnitude (MV)2.61[2]
Details[4]
Mass1.17±0.06 M
Radius4.49±0.13 R
Luminosity11.17[2] L
Surface gravity (log g)3.31±0.07 cgs
Temperature4,786±20 K
Metallicity [Fe/H]−0.03±0.03 dex
Rotational velocity (v sin i)1.51[5] km/s
Age6.20±1.18 Gyr
Other designations
64 Aql, BD−01° 3899, GC 27930, HD 191067, HIP 99171, HR 7690, SAO 144095[6]
Database references
SIMBADdata

This is an evolved giant star currently on the red giant branch[5] with a stellar classification of K1 III/IV.[3] The luminosity class of 'III/IV' indicates the spectrum shows a blend of features matching a subgiant and giant star. It is around 6.2 billion years old with 1.17 times the mass of the Sun and has expanded to 4.5 times the Sun's radius.[4] The star is radiating 11[2] times the Sun's luminosity from its enlarged photosphere at an effective temperature of 4,786 K.[4]

References

edit
  1. ^ a b c d e f 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.
  2. ^ a b c d e f Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  3. ^ a b Houk, N.; Swift, C. (1999), "Michigan catalogue of two-dimensional spectral types for the HD Stars", Michigan Spectral Survey, 5, Bibcode:1999MSS...C05....0H.
  4. ^ a b c d e Maldonado, J.; et al. (June 2013), "The metallicity signature of evolved stars with planets", Astronomy & Astrophysics, 554: 18, arXiv:1303.3418, Bibcode:2013A&A...554A..84M, doi:10.1051/0004-6361/201321082, S2CID 119289111, A84.
  5. ^ a b c Jones, M. I.; et al. (December 2011), "Study of the impact of the post-MS evolution of the host star on the orbits of close-in planets. I. Sample definition and physical properties", Astronomy & Astrophysics, 536: 7, arXiv:1110.6459, Bibcode:2011A&A...536A..71J, doi:10.1051/0004-6361/201117887, S2CID 55769003, A71.
  6. ^ "64 Aql". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved November 1, 2018.