Upsilon Aquilae

Summary

Upsilon Aquilae, Latinized from υ Aquilae, is the Bayer designation for a star in the equatorial constellation of Aquila. With an apparent visual magnitude of +5.91[4] it is a faint star but visible to the naked eye from suburban skies. It has an annual parallax shift of 18.66 mas,[1] indicating a distance of around 175 light-years (54 parsecs). The star is drifting closer with a radial velocity of –30 km/s.[5]

Upsilon Aquilae
Location of υ Aquilae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Aquila
Right ascension 19h 45m 39.94732s[1]
Declination +07° 36′ 47.3626″[1]
Apparent magnitude (V) +5.889[2]
Characteristics
Spectral type A3 IV[3]
U−B color index +0.09[4]
B−V color index +0.18[4]
Astrometry
Radial velocity (Rv)−29.9±2.0[5] km/s
Proper motion (μ) RA: +53.492[1] mas/yr
Dec.: +0.021[1] mas/yr
Parallax (π)18.6614 ± 0.0975 mas[1]
Distance174.8 ± 0.9 ly
(53.6 ± 0.3 pc)
Absolute magnitude (MV)+2.24[6]
Details
Mass1.81±0.02[7] M
Luminosity10.5[6] L
Surface gravity (log g)4.21[2] cgs
Temperature7,906[2] K
Metallicity [Fe/H]–0.05[2] dex
Rotational velocity (v sin i)42[7] km/s
Age180[8] Myr
Other designations
υ Aql, 49 Aquilae, BD+07° 4210, HD 186689, HIP 97229, HR 7519, SAO 125032[9]
Database references
SIMBADdata

Upsilon Aquilae is a subgiant star with a stellar classification of A3 IV.[3] The outer atmosphere is radiating energy into space with 10.5[6] times the Sun's luminosity from its photosphere at an effective temperature of 7,906 K,[2] which gives it the white-hot glow of an A-type star. It is 180[8] million years old with 1.8 times the mass of the Sun and is spinning relatively quickly with a projected rotational velocity of 42 km/s.[7]

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. Gaia DR2 record for this source at VizieR.
  2. ^ a b c d e Soubiran, C.; et al. (June 2010), "The PASTEL catalogue of stellar parameters", Astronomy and Astrophysics, 515: A111, arXiv:1004.1069, Bibcode:2010A&A...515A.111S, doi:10.1051/0004-6361/201014247, S2CID 118362423.
  3. ^ 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.
  4. ^ a b c Johnson, H. L.; et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory, 4 (99): 99, Bibcode:1966CoLPL...4...99J.
  5. ^ a b Wilson, Ralph Elmer (1953), "General catalogue of stellar radial velocities", Washington, Carnegie Institution of Washington: 0, Bibcode:1953GCRV..C......0W.
  6. ^ a b c 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.
  7. ^ a b c 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.
  8. ^ a b De Rosa, R. J.; et al. (2014), "The VAST Survey - III. The multiplicity of A-type stars within 75 pc", Monthly Notices of the Royal Astronomical Society, 437 (2): 1216–1240, arXiv:1311.7141, Bibcode:2014MNRAS.437.1216D, doi:10.1093/mnras/stt1932.
  9. ^ "* ups Aql". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2012-07-21.

External links edit

  • HR 7519
  • Image Upsilon Aquilae