Astronomy:Nu Andromedae

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Short description: Binary star in the constellation Andromeda
Nu Andromedae
Diagram showing star positions and boundaries of the Andromeda constellation and its surroundings
10px
Location of ν Andromedae (circled)
Observation data
Equinox J2000.0]] (ICRS)
Constellation Andromeda
Right ascension  00h 49m 48.846s[1]
Declination +41° 04′ 44.08″[1]
Apparent magnitude (V) 4.522[2]
Characteristics
Spectral type B4/5 V[3][4] + F8 V[5]
U−B color index –0.573[2]
B−V color index –0.136[2]
Astrometry
Radial velocity (Rv)–23.9[6] km/s
Proper motion (μ) RA: +21.711[1] mas/yr
Dec.: –18.694[1] mas/yr
Parallax (π)5.7868 ± 0.1857[1] mas
Distance560 ± 20 ly
(173 ± 6 pc)
Absolute magnitude (MV)−1.85[7]
Orbit[5]
Period (P)4.2827 d
Eccentricity (e)0.03
Longitude of the node (Ω)25.°
Periastron epoch (T)18,155.67
Semi-amplitude (K1)
(primary)
71.7 km/s
Semi-amplitude (K2)
(secondary)
101.9 km/s
Details
ν And A
Mass5.9±0.2[3] M
Radius3.4[8] R
Luminosity1,104[7] L
Surface gravity (log g)4.12±0.43[9] cgs
Temperature14,851±396[9] K
Metallicity [Fe/H]+0.14±0.17[9] dex
Rotational velocity (v sin i)20[10] km/s
Age63.1±17.9[3] Myr
Other designations
ν Andromedae, ν And, Nu And, 35 Andromedae, 35 And, BD+40 171, FK5 1021, HD 4727, HIP 3881, HR 226, SAO 36699, PPM 43365[11]
Database references
SIMBADdata

Nu Andromedae is a binary star system in the constellation Andromeda. Its Bayer designation is Latinized from ν Andromedae, and abbreviated Nu And or ν And, respectively. The system has an apparent visual magnitude of 4.5,[2] which is bright enough to be seen with the naked eye. Based on parallax measurements, it is located at a distance of approximately 560 light-years (170 parsecs) from Earth.[1] The pair are drifting closer with a heliocentric radial velocity of –24 km/s.[6] Situated just over a degree to the west of this star is the Andromeda Galaxy.[12]

Nu Andromedae is the prominent blue star in the upper right of this image. At the center is the Andromeda Galaxy.

Nu Andromedae is close spectroscopic binary[3] system with a period of 4.2828 days and a nearly circular orbit.[5] The primary component is a B-type main sequence star with a stellar classification of B5 V.[3] The fainter secondary has a classification of F8 V,[5] which makes it an F-type main sequence star. The pair is about 63 million years old.[3]

The pair have a peculiar velocity of 22.16±0.87 km/s relative to neighboring stars, which doesn't qualify it to be a runaway star system but does suggest it escaped its star cluster of origin. The trajectory indicates it may have left the NGC 6405 cluster some 25 million years ago.[13]

Naming

In Chinese, 奎宿 (Kuí Sù), meaning Legs (asterism), refers to an asterism consisting of ν Andromedae, η Andromedae, 65 Piscium, ζ Andromedae, ε Andromedae, δ Andromedae, π Andromedae, μ Andromedae, β Andromedae, σ Piscium, τ Piscium, 91 Piscium, υ Piscium, φ Piscium, χ Piscium and ψ1 Piscium. Consequently, the Chinese name for ν Andromedae itself is 奎宿七 (Kuí Sù qī, English: the Seventh Star of Legs.)[14]

References

  1. 1.0 1.1 1.2 1.3 1.4 Brown, A. G. A. (2021). "Gaia Early Data Release 3: Summary of the contents and survey properties". Astronomy & Astrophysics 649: A1. doi:10.1051/0004-6361/202039657. Bibcode2021A&A...649A...1G.  Gaia EDR3 record for this source at VizieR.
  2. 2.0 2.1 2.2 2.3 Oja, T. (April 1983), "UBV photometry of FK4 and FK4 supplement stars", Astronomy and Astrophysics Supplement Series 52: 131–134, Bibcode1983A&AS...52..131O. 
  3. 3.0 3.1 3.2 3.3 3.4 3.5 Tetzlaff, N.; Neuhäuser, R.; Hohle, M. M. (January 2011), "A catalogue of young runaway Hipparcos stars within 3 kpc from the Sun", Monthly Notices of the Royal Astronomical Society 410 (1): 190–200, doi:10.1111/j.1365-2966.2010.17434.x, Bibcode2011MNRAS.410..190T. 
  4. Nu Andromedae, a blue main-sequence star in Andromeda, http://www.astrostudio.org/xhip.php?hip=3881, retrieved 18 August 2014. 
  5. 5.0 5.1 5.2 5.3 Pourbaix, D. et al. (September 2004), "SB9: The ninth catalogue of spectroscopic binary orbits", Astronomy and Astrophysics 424 (2): 727–732, doi:10.1051/0004-6361:20041213, Bibcode2004A&A...424..727P. 
  6. 6.0 6.1 Wilson, R. E. (1953), "General Catalogue of Stellar Radial Velocities", Carnegie Institute Washington D.C. Publication (Carnegie Institute of Washington D.C.), Bibcode1953GCRV..C......0W. 
  7. 7.0 7.1 Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters 38 (5): 331, doi:10.1134/S1063773712050015, Bibcode2012AstL...38..331A. 
  8. Pasinetti Fracassini, L. E. et al. (February 2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS) - Third edition - Comments and statistics", Astronomy and Astrophysics 367 (2): 521–524, doi:10.1051/0004-6361:20000451, Bibcode2001A&A...367..521P. 
  9. 9.0 9.1 9.2 Koleva, M.; Vazdekis, A. (February 2012), "Stellar population models in the UV. I. Characterisation of the New Generation Stellar Library", Astronomy & Astrophysics 538: A143, doi:10.1051/0004-6361/201118065, Bibcode2012A&A...538A.143K. 
  10. Abt, Helmut A.; Levato, Hugo; Grosso, Monica (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal 573 (1): 359–365, doi:10.1086/340590, Bibcode2002ApJ...573..359A. 
  11. "35 And -- Star". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=35+And+--+Star. 
  12. Mollise, Rod (2006), The Urban Astronomer's Guide: A Walking Tour of the Cosmos for City Sky Watchers, Patrick Moore's Practical Astronomy Series, Springer, p. 178, ISBN 1846282160, https://books.google.com/books?id=Z0mvZk0s_TMC&pg=PA178. 
  13. Bhat, A. et al. (July 2022), "The origin of early-type runaway stars from open clusters", Astronomy & Astrophysics 663: id. A39, doi:10.1051/0004-6361/202142993, Bibcode2022A&A...663A..39B. 
  14. Script error: The function "in_lang" does not exist. AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日