41 Aquarii
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]
| 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[4] mas |
| Distance | 237 ± 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[5] mas |
| Distance | 241 ± 1 ly (73.9 ± 0.4 pc) |
| Details | |
| 41 Aqr A | |
| Radius | 7.88+0.09 −0.13[4] R☉ |
| Luminosity | 33.93±0.53[4] L☉ |
| Surface gravity (log g) | 2.85[6] cgs |
| Temperature | 4,750[6] K |
| Metallicity [Fe/H] | –0.13[6] dex |
| 41 Aqr B | |
| Radius | 1.76+0.29 −0.06[5] R☉ |
| Luminosity | 6.319±0.043[5] L☉ |
| Temperature | 6,899+115 −506[5] K |
| Other designations | |
| Database references | |
| SIMBAD | data |
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
- 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.
- 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.
- 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.
- 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.
- 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.
- 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.
- "41 Aqr -- Star in double system", SIMBAD Astronomical Database, Centre de Données astronomiques de Strasbourg, retrieved 2012-02-23.
- 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.
