41 Aquarii is a double star[3] in the equatorial constellation of Aquarius. 41 Aquarii is its Flamsteed designation. It is visible to the naked eye as a dim, orange-hued point of light with a combined apparent visual magnitude of 5.354.[2] The pair are located at a distance of around 239 light-years (73 parsecs) from the Sun based on parallax, but are drifting closer with a radial velocity of –25 km/s.[4]

41 Aquarii
Observation data
Epoch J2000      Equinox J2000
Constellation Aquarius
Right ascension 22h 14m 18.03271s[1]
Declination –21° 04′ 28.4330″[1]
Apparent magnitude (V) 5.354[2]
Characteristics
Spectral type K0 III + F8 V[3]
U−B color index +0.465[2]
B−V color index +0.834[2]
Astrometry
41 Aqr A
Radial velocity (Rv)−24.94±0.13[4] km/s
Proper motion (μ) RA: +24.827[4] mas/yr
Dec.: +54.923[4] mas/yr
Parallax (π)13.7811 ± 0.1850 mas[4]
Distance237 ± 3 ly
(72.6 ± 1.0 pc)
Proper motion (μ) RA: +27.266[5] mas/yr
Dec.: +57.272[5] mas/yr
Parallax (π)13.5404 ± 0.0719 mas[5]
Distance241 ± 1 ly
(73.9 ± 0.4 pc)
Details
41 Aqr A
Radius7.88+0.09
−0.13
[4] R
Luminosity33.93±0.53[4] L
Surface gravity (log g)2.85[6] cgs
Temperature4,750[6] K
Metallicity [Fe/H]–0.13[6] dex
41 Aqr B
Radius1.76+0.29
−0.06
[5] R
Luminosity6.319±0.043[5] L
Temperature6,899+115
−506
[5] K
Other designations
41 Aqr, BD–21°6180, HD 210960, HIP 109786, HR 8480, SAO 190986, WDS J22143-2104[7]
Database references
SIMBADdata

The brighter component of the pair is a red clump[8] giant star with a stellar classification of K0 III[3] and a magnitude of 5.73. This is an aging star that has exhausted the supply of hydrogen at its core and is now generating energy through core helium fusion. It has eight[4] times the girth of the Sun and is radiating 34[4] times the luminosity of the Sun at an effective temperature of 4,750 K.[6]

At an angular separation of 5.148 arcseconds, the fainter companion is an F-type main sequence star with a magnitude 7.16 and a classification of F8 V.[3] It has 1.8[5] times the Sun's radius and is radiating six[5] times the Sun's luminosity from its photosphere at 6,899 K.[5]

References

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  1. ^ a b 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, S2CID 18759600.
  2. ^ a b c d Rakos, K. D.; et al. (February 1982), "Photometric and astrometric observations of close visual binaries", Astronomy and Astrophysics Supplement Series, 47: 221–235, Bibcode:1982A&AS...47..221R.
  3. ^ a b c d 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  4. ^ 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.
  5. ^ 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.
  6. ^ a b c d McWilliam, Andrew (December 1990), "High-resolution spectroscopic survey of 671 GK giants", Astrophysical Journal Supplement Series, 74: 1075–1128, Bibcode:1990ApJS...74.1075M, doi:10.1086/191527.
  7. ^ "41 Aqr -- Star in double system", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2012-02-23.
  8. ^ Alves, David R. (August 2000), "K-Band Calibration of the Red Clump Luminosity", The Astrophysical Journal, 539 (2): 732–741, arXiv:astro-ph/0003329, Bibcode:2000ApJ...539..732A, doi:10.1086/309278, S2CID 16673121.