Astronomy:44 Aquarii

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Short description: Star in the constellation Aquarius
44 Aquarii
Observation data
Equinox J2000.0]] (ICRS)
Constellation Aquarius
Right ascension  22h 17m 06.49946s[1]
Declination −05° 23′ 13.8000″[1]
Apparent magnitude (V) 5.75[2]
Characteristics
Evolutionary stage horizontal branch[3]
Spectral type G6 III[4]
U−B color index +0.51[2]
B−V color index +0.88[2]
Variable type suspected[5]
Astrometry
Radial velocity (Rv)+7.4[6] km/s
Proper motion (μ) RA: −6.05[7] mas/yr
Dec.: +18.67[7] mas/yr
Parallax (π)9.7114 ± 0.0934[1] mas
Distance336 ± 3 ly
(103.0 ± 1.0 pc)
Absolute magnitude (MV)+0.51[4]
Details
Mass2.53[4] M☉
Radius9.14+0.38
−0.34
[1] R☉
Luminosity53.169±0.628[1] L☉
Surface gravity (log g)2.70[8] cgs
Temperature5,025[8] K
Metallicity [Fe/H]−0.31[8] dex
Rotational velocity (v sin i)1.8±0.8[9] km/s
Age537[4] Myr
Other designations
44 Aqr, NSV 14100, BD−06°5960, FK5 3782, HD 211434, HIP 110023, HR 8504, SAO 145993[10]
Database references
SIMBADdata

44 Aquarii is a single[11] star located 336[1] light years away from the Sun in the equatorial constellation of Aquarius. 44 Aquarii is its Flamsteed designation.[10] It is visible to the naked eye as a dim, yellow-hued star with an apparent visual magnitude of 5.75.[2] This body is moving away from the Earth with a heliocentric radial velocity of +7.4 km/s.[6]

A stellar classification of G6 III[4] indicates this is an evolved giant star, most likely (98% chance) on the horizontal branch,[3] having exhausted the hydrogen at its core and expanded. It is a suspected variable star of unknown type.[5] 44 Aquarii is 537[4] million years old with about 2.53[4] times the mass of the Sun and 9[1] times the Sun's radius. The star is radiating 62[4] times the Sun's luminosity from its photosphere at an effective temperature of 5,025 K.[8] At this heat, the star has the golden-hued glow of a G-type star.

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 Brown, A. G. A. (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics 616: A1. doi:10.1051/0004-6361/201833051. Bibcode: 2018A&A...616A...1G.  Gaia DR2 record for this source at VizieR.
  2. ↑ 2.0 2.1 2.2 2.3 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. 
  3. ↑ 3.0 3.1 Stock, Stephan et al. (August 2018), "Precise radial velocities of giant stars. X. Bayesian stellar parameters and evolutionary stages for 372 giant stars from the Lick planet search", Astronomy & Astrophysics 616: 15, doi:10.1051/0004-6361/201833111, A33, Bibcode: 2018A&A...616A..33S. 
  4. ↑ 4.0 4.1 4.2 4.3 4.4 4.5 4.6 4.7 Takeda, Yoichi; Sato, Bun'ei; Murata, Daisuke (August 2008), "Stellar Parameters and Elemental Abundances of Late-G Giants", Publications of the Astronomical Society of Japan 60 (4): 781–802, doi:10.1093/pasj/60.4.781, Bibcode: 2008PASJ...60..781T. 
  5. ↑ 5.0 5.1 Samus, N. N. et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1 61 (1): 80–88, doi:10.1134/S1063772917010085, Bibcode: 2017ARep...61...80S. 
  6. ↑ 6.0 6.1 Wielen, R. et al. (1999), "Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions", Veröff. Astron. Rechen-Inst. Heidelb (Astronomisches Rechen-Institut Heidelberg) 35 (35): 1, Bibcode: 1999VeARI..35....1W. 
  7. ↑ 7.0 7.1 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode: 2007A&A...474..653V. 
  8. ↑ 8.0 8.1 8.2 8.3 Soubiran, C. et al. (June 2010), "The PASTEL catalogue of stellar parameters", Astronomy and Astrophysics 515: A111, doi:10.1051/0004-6361/201014247, Bibcode: 2010A&A...515A.111S. 
  9. ↑ Gray, David F. (1989), "The rotational break for G giants", Astrophysical Journal 347: 1021–1029, doi:10.1086/168192, Bibcode: 1989ApJ...347.1021G. 
  10. ↑ 10.0 10.1 "* 44 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+44+Aqr. 
  11. ↑ Eggleton, P. P.; Tokovinin, A. A. (2008), "A catalogue of multiplicity among bright stellar systems", Monthly Notices of the Royal Astronomical Society 389 (2): 869, doi:10.1111/j.1365-2966.2008.13596.x, Bibcode: 2008MNRAS.389..869E.