22 Aquilae, abbreviated 22 Aql, is a star in the equatorial constellation of Aquila. 22 Aquilae is its Flamsteed designation. It is a faint star but visible to the naked eye with an apparent visual magnitude of 5.59.[2] The distance to 22 Aql can be estimated from its annual parallax shift of 4.74 mas,[1] which yields a separation of 690 light years. It is moving closer to the Earth with a heliocentric radial velocity of −23 km/s.[5]

22 Aquilae
Observation data
Epoch J2000      Equinox J2000
Constellation Aquila
Right ascension 19h 16m 31.03180s[1]
Declination +04° 50′ 05.2523″[1]
Apparent magnitude (V) 5.59[2]
Characteristics
Spectral type A1 V[3] or A3 IV[4]
B−V color index 0.101±0.006[2]
Astrometry
Radial velocity (Rv)−22.8±4.3[5] km/s
Proper motion (μ) RA: +14.306[1] mas/yr
Dec.: –11.083[1] mas/yr
Parallax (π)4.7392 ± 0.0910 mas[1]
Distance690 ± 10 ly
(211 ± 4 pc)
Absolute magnitude (MV)−0.48[2]
Details
Mass2.89±0.11[6] M
Luminosity161+27
−23
[6] L
Temperature8453±78[6] K
Rotational velocity (v sin i)70[6] km/s
Other designations
22 Aql, AG+04 2489, BD+04° 4045, GC 26567, HD 180482, HIP 94727, HR 7303, SAO 143134, 2MASS J19163102+0450052[7]
Database references
SIMBADdata

Cowley et al. (1969) assigned this star a stellar classification of A3 IV,[4] matching an evolving subgiant star that has exhausted the hydrogen at its core. Houk and Swift (1999) reassigned it as an A-type main-sequence star with a class of A1 V.[3] It has nearly three times the mass of the Sun and is spinning with a projected rotational velocity of 70 km/s.[6] The star is radiating 161[6] times the Sun's luminosity from its photosphere at an effective temperature of 8,453 K.[6]

References

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  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 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 Cowley, A.; et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal, 74: 375–406, Bibcode:1969AJ.....74..375C, doi:10.1086/110819.
  5. ^ a b Gontcharov, G. A. (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, S2CID 119231169.
  6. ^ a b c d e f g Zorec, J.; Royer, F. (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy & Astrophysics, 537: A120, arXiv:1201.2052, Bibcode:2012A&A...537A.120Z, doi:10.1051/0004-6361/201117691, S2CID 55586789.
  7. ^ "22 Aql". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved October 31, 2018.