Astronomy:51 Aquarii

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Short description: Binary star system in the constellation Aquarius
51 Aquarii
Observation data
Equinox J2000.0]] (ICRS)
Constellation Aquarius
Right ascension  22h 24m 06.88433s[1]
Declination –04° 50′ 13.2692″[1]
Apparent magnitude (V) 5.78 (6.45 + 6.63)[2]
Characteristics
Spectral type A0 V[3] + A0[2]
U−B color index –0.11[4]
B−V color index –0.04[4]
Astrometry
Radial velocity (Rv)+6[5] km/s
Proper motion (μ) RA: +26.90[1] mas/yr
Dec.: –7.35[1] mas/yr
Parallax (π)8.04 ± 0.63[1] mas
Distance410 ± 30 ly
(124 ± 10 pc)
Orbit[6]
Period (P)145.07±1.85 yr
Semi-major axis (a)0.402±0.003
Eccentricity (e)0.702±0.003
Inclination (i)161.4±0.7°
Longitude of the node (Ω)113.5±3.0°
Periastron epoch (T)1987.66±0.05
Argument of periastron (ω)
(secondary)
296.9±3.0°
Details
51 Aqr A
Mass2.80±0.10[7] M
Luminosity88.2+14.8
−14.2
[7] L
Temperature10,328±71[7] K
Rotational velocity (v sin i)91[7] km/s
Other designations
51 Aqr, BD−05°5780, HD 212404, HIP 110578, HR 8533, SAO 146067, WDS J22241-0450[8]
Database references
SIMBADdata

61 Aquarii is a binary star[2] system located around 410[1] light years away from the Sun in the equatorial constellation of Aquarius. 51 Aquarii is its Flamsteed designation. It is visible to the naked eye as a dim, yellow-white hued star with a combined apparent visual magnitude of 5.78.[4] The system is moving further from the Earth with a heliocentric radial velocity of +6 km/s.[5]

The dual nature of this system was discovered by S. W. Burnham in 1873 with a 6 inches (15 cm) Alvan Clark refractor.[9] The pair orbit each other with a period of 145 years and a large eccentricity of 0.7.[6] The magnitude 6.45[2] primary, designated component A, is an A-type main sequence star with a stellar classification of A0 V.[3] It has a high rate of rotation with a projected rotational velocity of 91 km/s.[10] The secondary component has a matching class of A0 with a visual magnitude of 6.63.[2] It has an effective temperature of 10,238 K.

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 2.3 2.4 Eggleton, P. P.; Tokovinin, A. A. (September 2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869–879, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode2008MNRAS.389..869E. 
  3. 3.0 3.1 Cowley, A. et al. (April 1969), "A study of the bright A stars. I. A catalogue of spectral classifications", Astronomical Journal 74: 375–406, doi:10.1086/110819, Bibcode1969AJ.....74..375C. 
  4. 4.0 4.1 4.2 Nicolet, B. (1978), "Photoelectric photometric Catalogue of homogeneous measurements in the UBV System", Astronomy and Astrophysics Supplement Series 34: 1–49, Bibcode1978A&AS...34....1N. 
  5. 5.0 5.1 Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication (Carnegie Institute of Washington, D.C.), Bibcode1953GCRV..C......0W. 
  6. 6.0 6.1 Tokovinin, Andrei; Mason, Brian D.; Hartkopf, William I.; Mendez, Rene A.; Horch, Elliott P. (2015), "Speckle Interferometry at Soar in 2014", The Astronomical Journal 150 (2): 50, doi:10.1088/0004-6256/150/2/50, Bibcode2015AJ....150...50T. 
  7. 7.0 7.1 7.2 7.3 Zorec, J.; Royer, F.; Asplund, Martin; Cassisi, Santi; Ramirez, Ivan; Melendez, Jorge; Bensby, Thomas; Feltzing, Sofia (2012), "Rotational velocities of A-type stars. IV. Evolution of rotational velocities", Astronomy and Astrophysics 537: A120, doi:10.1051/0004-6361/201117691, Bibcode2012A&A...537A.120Z. 
  8. "* 51 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+51+Aqr. 
  9. Docobo, J. A.; Ling, J. F. (April 2007), "Orbits and System Masses of 14 Visual Double Stars with Early-Type Components", The Astronomical Journal 133 (4): 1209–1216, doi:10.1086/511070, Bibcode2007AJ....133.1209D 
  10. 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, doi:10.1051/0004-6361:20065224, Bibcode2007A&A...463..671R. 

External links