42 Aquarii

Summary

42 Aquarii is a single[8] star located 447 light years away from the Sun in the zodiac constellation of Aquarius. 42 Aquarii is its Flamsteed designation. It is visible to the naked eye as a faint, orange-hued star with an apparent visual magnitude of 5.34.[2] This object is moving further from the Sun with a heliocentric radial velocity of around +13 km/s.[2]

42 Aquarii
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Aquarius
Right ascension 22h 16m 48.04643s[1]
Declination −12° 49′ 53.1673″[1]
Apparent magnitude (V) 5.34[2]
Characteristics
Evolutionary stage giant
Spectral type K1 III[3]
B−V color index 1.132±0.001[2]
Astrometry
Radial velocity (Rv)+13.0±4.2[2] km/s
Proper motion (μ) RA: +1.89[4] mas/yr
Dec.: +5.03[4] mas/yr
Parallax (π)7.3032 ± 0.1451 mas[1]
Distance447 ± 9 ly
(137 ± 3 pc)
Absolute magnitude (MV)−0.93[2]
Details
Mass3.14±0.27[5] M
Radius11.24+0.23
−0.32
[1] R
Luminosity69.950±3.907[1] L
Surface gravity (log g)2.90[6] cgs
Temperature4,980+71
−51
[1] K
Metallicity [Fe/H]+0.00±0.04[2] dex
Rotational velocity (v sin i)3.43[6] km/s
Age470±150[5] Myr
Other designations
42 Aqr, BD−13°6148, HD 211361, HIP 110000, HR 8496, SAO 164974[7]
Database references
SIMBADdata

This object is an evolved giant star with a stellar classification of K1 III,[3] most likely (82% chance) on the horizontal branch.[5] It is around 470[5] million years old with a projected rotational velocity of 3.4 km/s.[6] The star has over three[5] times the mass of the Sun and has expanded to 11[1] times the Sun's radius. It is radiating 70[1] times the luminosity of the Sun from its enlarged photosphere at an effective temperature of 4,980 K.[1]

References edit

  1. ^ a b c d e f g h i 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 f g 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.
  3. ^ a b Houk, Nancy; Smith-Moore, M. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 4, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1988mcts.book.....H.
  4. ^ a b van Leeuwen, F. (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, S2CID 18759600.
  5. ^ a b c d e Reffert, Sabine; et al. (2015), "Precise radial velocities of giant stars. VII. Occurrence rate of giant extrasolar planets as a function of mass and metallicity", Astronomy & Astrophysics, 574: A116, arXiv:1412.4634, Bibcode:2015A&A...574A.116R, doi:10.1051/0004-6361/201322360, hdl:10722/215277, S2CID 59334290.
  6. ^ a b c Hekker, S.; Meléndez, J. (2007), "Precise radial velocities of giant stars. III. Spectroscopic stellar parameters", Astronomy and Astrophysics, 475 (3): 1003, arXiv:0709.1145, Bibcode:2007A&A...475.1003H, doi:10.1051/0004-6361:20078233, S2CID 10436552.
  7. ^ "42 Aqr". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2019-05-16.
  8. ^ 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.