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
Spectral type G6 III[3]
U−B color index +0.51[2]
B−V color index +0.88[2]
Variable type suspected[4]
Astrometry
Radial velocity (Rv)+7.4[5] km/s
Proper motion (μ) RA: –6.05[6] mas/yr
Dec.: +18.67[6] mas/yr
Parallax (π)9.7114 ± 0.0934[1] mas
Distance336 ± 3 ly
(103.0 ± 1.0 pc)
Absolute magnitude (MV)+0.51[3]
Details
Mass2.53[3] M
Radius9.14+0.38
−0.34
[1] R
Luminosity53.169±0.628[1] L
Surface gravity (log g)2.70[7] cgs
Temperature5,025[7] K
Metallicity [Fe/H]–0.31[7] dex
Rotational velocity (v sin i)1.8±0.8[8] km/s
Age537[3] Myr
Other designations
44 Aqr, NSV 14100, BD−06°5960, FK5 3782, HD 211434, HIP 110023, HR 8504, SAO 145993[9]
Database references
SIMBADdata

44 Aquarii is a single[10] star located 336[1] light years away from the Sun in the equatorial constellation of Aquarius. 44 Aquarii is its Flamsteed designation.[9] 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.[5]

A stellar classification of G6 III[3] indicates this is an evolved giant star, most likely (98% chance) on the horizontal branch,[11] having exhausted the hydrogen at its core and expanded. It is a suspected variable star of unknown type.[4] 44 Aquarii is 537[3] million years old with about 2.53[3] times the mass of the Sun and 9[1] times the Sun's radius. The star is radiating 62[3] times the Sun's luminosity from its photosphere at an effective temperature of 5,025 K.[7] 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. Bibcode2018A&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, Bibcode1966CoLPL...4...99J. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 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, Bibcode2008PASJ...60..781T. 
  4. 4.0 4.1 Samus, N. N. et al. (2017), "General Catalogue of Variable Stars", Astronomy Reports, 5.1 61 (1): 80–88, doi:10.1134/S1063772917010085, Bibcode2017ARep...61...80S. 
  5. 5.0 5.1 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, Bibcode1999VeARI..35....1W. 
  6. 6.0 6.1 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  7. 7.0 7.1 7.2 7.3 Soubiran, C. et al. (June 2010), "The PASTEL catalogue of stellar parameters", Astronomy and Astrophysics 515: A111, doi:10.1051/0004-6361/201014247, Bibcode2010A&A...515A.111S. 
  8. Gray, David F. (1989), "The rotational break for G giants", Astrophysical Journal 347: 1021–1029, doi:10.1086/168192, Bibcode1989ApJ...347.1021G. 
  9. 9.0 9.1 "* 44 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+44+Aqr. 
  10. 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, Bibcode2008MNRAS.389..869E. 
  11. 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, Bibcode2018A&A...616A..33S. 

External links