41 G. Arae

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41 G. Arae
Observation data
Epoch J2000      Equinox J2000
Constellation Ara
Right ascension 17h 19m 03.83755s[1]
Declination −46° 38′ 10.4404″[1]
Apparent magnitude (V) 5.48[2] (5.61 / 8.88)[3]
Characteristics
Spectral type G8V + M0V[4]
U−B color index +0.38[5]
B−V color index +0.80[6]
R−I color index +0.41[6]
Astrometry
Radial velocity (Rv)25.96±0.14[1] km/s
Proper motion (μ) RA: 1029.610 mas/yr[1]
Dec.: 106.935 mas/yr[1]
Parallax (π)113.7513 ± 0.0725 mas[1]
Distance28.67 ± 0.02 ly
(8.791 ± 0.006 pc)
Absolute magnitude (MV)5.74[7]
Orbit[3]
Companion41 G. Ara B
Period (P)953 yr
Semi-major axis (a)13.341″
Eccentricity (e)0.825
Inclination (i)40.5°
Longitude of the node (Ω)137.3°
Periastron epoch (T)1907.5
Argument of periastron (ω)
(secondary)
329.7°
Details
41 G. Ara A
Mass0.810[8] M
Radius0.79[8] R
Luminosity0.42[citation needed] L
Surface gravity (log g)4.5[6] cgs
Temperature5,305[6] K
Metallicity [Fe/H]−0.35[6] dex
Rotational velocity (v sin i)4.5[9] km/s
Age5.5–6.3[10] Gyr
41 G. Ara B
Mass0.52[4] M
Radius0.650[4] R
Other designations
41 G. Arae, CD-46° 11370, GJ 666, HD 156274, HIP 84720, HR 6416, LHS 444, LTT 6886, SAO 227816, LPM 636, LFT 1334.
Database references
SIMBAD41 G. Ara
41 G. Ara A
41 G. Ara B
ARICNS41 G. Ara A
41 G. Ara B

41 G. Arae (abbreviated to 41 G. Ara), also known as GJ 666, is a trinary star system in the constellation Ara 28.7 light-years (8.8 parsecs) from the Sun. Although often called just 41 Arae, it is more accurate to call it 41 G. Arae, as the number 41 is the Gould designation (Flamsteed only covered the northern hemisphere).

The primary star in this system is a G-type main sequence star with a stellar classification of G8V. It has about 81% of the mass of the Sun, and 79% of the Sun's radius.[8] The fainter member of the pair, a red dwarf,[4] has a peculiar spectrum that shows a deficiency in elements with a higher atomic number than Helium. No planetary companions have been detected in orbit around these stars.[11]

The two stars share a highly elliptical orbit that takes several centuries to complete. The estimates of the period range from 693 to 2,200 years,[12] and the average separation of the two stars is about 210 AU (or 210 times the average distance between the Earth and the Sun).

41 G. Arae is most likely a triple, comprising the following components: Gliese 666A supposed as a spectroscopic binary, and Gliese 666B as its companion. Two other visual companions were proposed, but neither share the system's motion.[13] Observations from Gaia have shown that it is in fact component B which is binary, with an orbital period of 88 days.[14]

This system has a relatively high proper motion, moving over a second of arc across the sky each year. The space velocity components of this system are [U, V, W] = [+38, +30, −19] km/s.[6] The stars in this system show low chromospheric activity, and have a net space velocity of 52 km/s relative to the Sun. This, in combination with their low metallicity, shows that the pair belongs to the old disk population.[6]

See also[edit]

References[edit]

  1. ^ a b c d e Vallenari, A.; et al. (Gaia collaboration) (2023). "Gaia Data Release 3. Summary of the content and survey properties". Astronomy and Astrophysics. 674: A1. arXiv:2208.00211. Bibcode:2023A&A...674A...1G. doi:10.1051/0004-6361/202243940. S2CID 244398875. Gaia DR3 record for this source at VizieR.
  2. ^ Ducati, J. R. (2002). "VizieR Online Data Catalog: Catalogue of Stellar Photometry in Johnson's 11-color system". CDS/ADC Collection of Electronic Catalogues. 2237. Bibcode:2002yCat.2237....0D.
  3. ^ a b "Entry 171903.85-463810.1", Sixth Catalog of Orbits of Visual Binary Stars, United States Naval Observatory, archived from the original on 2017-08-01, retrieved 2016-06-07.
  4. ^ a b c d Zakhozhaj, V. A. (1979). "Nearest stars". Vestnik Khar'kovskogo Universiteta. 190. SIMBAD: 52–77. Bibcode:1979VKha..190...52Z.
  5. ^ Johnson, H. L. (1966). "UBVRIJKL Photometry of the Bright Stars". Communications of the Lunar and Planetary Laboratory. 4: 99. Bibcode:1966CoLPL...4...99J.
  6. ^ a b c d e f g Perrin, M.-N.; de Strobel, G. Cayrel; Dennefeld, M. (1988), "High S/N detailed spectral analysis of four G and K dwarfs within 10 PC of the sun", Astronomy and Astrophysics, 191 (2): 237–247, Bibcode:1988A&A...191..237P
  7. ^ Holmberg, J.; et al. (July 2009), "The Geneva-Copenhagen survey of the solar neighbourhood. III. Improved distances, ages, and kinematics", Astronomy and Astrophysics, 501 (3): 941–947, arXiv:0811.3982, Bibcode:2009A&A...501..941H, doi:10.1051/0004-6361/200811191, S2CID 118577511.
  8. ^ a b c Takeda, G.; et al. (February 2007) [2006], "Structure and Evolution of Nearby Stars with Planets II. Physical Properties of ~ 1000 Cool Stars from the SPOCS Catalog", The Astrophysical Journal Supplement Series, 168 (2): 297–318, arXiv:astro-ph/0607235, Bibcode:2007ApJS..168..297T, doi:10.1086/509763, S2CID 18775378
  9. ^ Schröder, C.; Reiners, Ansgar; Schmitt, Jürgen H. M. M. (January 2009), "Ca II HK emission in rapidly rotating stars. Evidence for an onset of the solar-type dynamo" (PDF), Astronomy and Astrophysics, 493 (3): 1099–1107, Bibcode:2009A&A...493.1099S, doi:10.1051/0004-6361:200810377[permanent dead link]
  10. ^ Mamajek, Eric E.; Hillenbrand, Lynne A. (November 2008), "Improved Age Estimation for Solar-Type Dwarfs Using Activity-Rotation Diagnostics", The Astrophysical Journal, 687 (2): 1264–1293, arXiv:0807.1686, Bibcode:2008ApJ...687.1264M, doi:10.1086/591785, S2CID 27151456
  11. ^ Santos, N. C.; et al. (July 2005), "Spectroscopic metallicities for planet-host stars: Extending the samples", Astronomy and Astrophysics, 437 (3): 1127–1133, arXiv:astro-ph/0504154, Bibcode:2005A&A...437.1127S, doi:10.1051/0004-6361:20052895, S2CID 16256304
  12. ^ de Mello, G. F. Porto; del Peloso, E. F.; Ghezzi, L. (2006), "Astrobiologically interesting stars within 10 parsecs of the Sun", Astrobiology, 6 (2): 308–331, arXiv:astro-ph/0511180, Bibcode:2006AsBio...6..308P, doi:10.1089/ast.2006.6.308, PMID 16689649, S2CID 119459291
  13. ^ Jenkins, J. S.; Díaz, M.; Jones, H. R. A.; Butler, R. P.; Tinney, C. G.; O'Toole, S. J.; Carter, B. D.; Wittenmyer, R. A.; Pinfield, D. J. (2015). "The observed distribution of spectroscopic binaries from the Anglo-Australian Planet Search". Monthly Notices of the Royal Astronomical Society. 453 (2): 1439. arXiv:1507.04749. Bibcode:2015MNRAS.453.1439J. doi:10.1093/mnras/stv1596.
  14. ^ Reylé, Céline; Jardine, Kevin; Fouqué, Pascal; Caballero, Jose A.; Smart, Richard L.; Sozzetti, Alessandro (6 February 2023). The 10 parsec sample in the Gaia era: First update. The 21st Cambridge workshop on Cool Stars, Stellar Systems, and the Sun. arXiv:2302.02810. doi:10.5281/zenodo.7576096.

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