Omega2 Aquilae

For other star systems with this Bayer designation, see Omega Aquilae.
Omega2 Aquilae
Diagram showing star positions and boundaries of the Aquila constellation and its surroundings


Location of ω2 (circled)

Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Aquila
Right ascension 19h 19m 53.06650s[1]
Declination +11° 32 05.8750[1]
Apparent magnitude (V) 6.023[2]
Characteristics
Spectral type A2 V[3]
U−B color index +0.07[4]
B−V color index +0.08[4]
Astrometry
Radial velocity (Rv)−26[5] km/s
Proper motion (μ) RA: 43.77[1] mas/yr
Dec.: 22.57[1] mas/yr
Parallax (π)12.27 ± 0.52[1] mas
Distance270 ± 10 ly
(81 ± 3 pc)
Details
Radius2.0[6] R
Temperature8,936[7] K
Rotational velocity (v sin i)154[8] km/s
Other designations
29 Aquilae, 29 Aql, BD+11 3802, GC 26660, HD 181383, HIP 95002, HR 7332, PPM 136128, SAO 104728.[2]

Omega2 Aquilae (ω2 Aquilae, ω2 Aql) is the Bayer designation for a star in the equatorial constellation of Aquila, the eagle. It has an apparent visual magnitude of 6.0,[2] which is close to the lower limit of detectability with the naked eye. According to the Bortle Dark-Sky Scale, this star can be viewed from dark rural skies. As the Earth orbits about the Sun, this star undergoes a parallax shift of 12.27 mas.[1] This is equivalent to a physical distance of 270 light-years (83 parsecs) from Earth, give or take a 10 light year margin of error.

Analysis of the spectrum of this star shows it to match a stellar classification of A2 V,[3] indicating it is an A-type main sequence star. It is about double[6] the size of the Sun. The outer atmosphere is radiating energy at an effective temperature of 8,936 K,[7] giving it the white hue of an A-type star.[9] Omega2 Aquilae is spinning rapidly with a projected rotational velocity of 154 km/s.[8]

References

  1. 1 2 3 4 5 6 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.
  2. 1 2 3 "29 Aql -- Star", SIMBAD Astronomical Object Database (Centre de Données astronomiques de Strasbourg), retrieved 2012-07-21.
  3. 1 2 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. 1 2 Osawa, K.; Hata, S. (1962), "Three-color photometry of B8-A2 stars (II).", Annals of the Tokyo Astronomical Observatory 7: 209, Bibcode:1962AnTok...7..209O.
  5. Evans, D. S. (June 20–24, 1966), "The Revision of the General Catalogue of Radial Velocities", in Batten, Alan Henry; Heard, John Frederick, Determination of Radial Velocities and their Applications, Proceedings from IAU Symposium no. 30, University of Toronto: International Astronomical Union, Bibcode:1967IAUS...30...57E.
  6. 1 2 Pasinetti Fracassini, L. E.; et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics", Astronomy and Astrophysics 367: 521–524, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451.
  7. 1 2 Soubiran, C.; Le Campion, J.-F.; Cayrel de Strobel, G.; Caillo, A. (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.
  8. 1 2 Royer, F.; Zorec, J.; Gómez, A. E. (February 2007), "Rotational velocities of A-type stars. III. Velocity distributions", Astronomy and Astrophysics 463 (2): 671–682, arXiv:astro-ph/0610785, Bibcode:2007A&A...463..671R, doi:10.1051/0004-6361:20065224.
  9. "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, retrieved 2012-01-16.

External links

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