Nu Andromedae

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Not to be confused with V Andromedae, Andromeda V, or 5 Andromedae. ‹See Tfd›
"ν And" redirects here. For other uses, see Vand.
Nu Andromedae
Diagram showing star positions and boundaries of the Andromeda constellation and its surroundings
Cercle rouge 100%.svg

Location of ν Andromedae (circled)
Observation data
Epoch J2000      Equinox J2000
Constellation Andromeda
Right ascension 00h 49m 48.84737s[1]
Declination +41° 04′ 44.0764″[1]
Apparent magnitude (V) 4.522[2]
Characteristics
Spectral type B5 V[3] + F8 V[4]
U−B color index –0.573[2]
B−V color index –0.136[2]
Astrometry
Radial velocity (Rv) –23.9[5] km/s
Proper motion (μ) RA: +22.77[1] mas/yr
Dec.: –18.35[1] mas/yr
Parallax (π) 5.28 ± 0.15[1] mas
Distance 620 ± 20 ly
(189 ± 5 pc)
Orbit[4]
Period (P) 4.2827 d
Eccentricity (e) 0.03
Longitude of the node (Ω) 25.°
Periastron epoch (T) 18155.67
Semi-amplitude (K1)
(primary)
71.7 km/s
Semi-amplitude (K2)
(secondary)
101.9 km/s
Details
ν And A
Mass 5.9 ± 0.2[3] M
Radius 3.4[6] R
Surface gravity (log g) 4.12 ± 0.43[7] cgs
Temperature 14,851 ± 396[7] K
Metallicity [Fe/H] +0.14 ± 0.17[7] dex
Rotational velocity (v sin i) 20[8] km/s
Age 63.1 ± 17.9[3] Myr
Other designations
ν Andromedae, ν And, Nu And, Nu Andromedae 35 Andromedae, 35 And, BD+40 171, FK5 1021, HD 4727, HIP 3881, HR 226, SAO 36699.[9]

Nu Andromedae (Nu And, ν Andromedae, ν And) is a binary star in the constellation Andromeda. The system has an apparent visual magnitude of 4.5,[2] which is bright enough to be seen with the naked eye. It is approximately 620 light-years (190 parsecs) from Earth.[1] Situated just over a degree to the west of this star is the Andromeda Galaxy.[10]

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

Nu Andromedae is spectroscopic binary[3] system with a nearly circular orbit that has a period of 4.2828 days.[4] 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,[4] which makes it an F-type main sequence star. The pair are about 63 million years old.[3]

Naming[edit]

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, ν Andromedae itself is known as 奎宿七 (Kuí Sù qī, English: the Seventh Star of Legs.)[11]

References[edit]

  1. ^ a b c d e f 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. 
  2. ^ a b c d Oja, T. (April 1983), "UBV photometry of FK4 and FK4 supplement stars", Astronomy and Astrophysics Supplement Series 52: 131–134, Bibcode:1983A&AS...52..131O. 
  3. ^ a b c d e f 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, arXiv:1007.4883, Bibcode:2011MNRAS.410..190T, doi:10.1111/j.1365-2966.2010.17434.x. 
  4. ^ a b c d Pourbaix, D. et al. (September 2004), "SB9: The ninth catalogue of spectroscopic binary orbits", Astronomy and Astrophysics 424: 727–732, arXiv:astro-ph/0406573, Bibcode:2004A&A...424..727P, doi:10.1051/0004-6361:20041213. 
  5. ^ Wilson, R. E. (1953), General Catalogue of Stellar Radial Velocities, Carnegie Institute of Washington D.C., Bibcode:1953GCRV..C......0W. 
  6. ^ 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, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451. 
  7. ^ a b c Koleva, M.; Vazdekis, A. (February 2012), "Stellar population models in the UV. I. Characterisation of the New Generation Stellar Library", Astronomy & Astrophysics 538: A143, arXiv:1111.5449, Bibcode:2012A&A...538A.143K, doi:10.1051/0004-6361/201118065. 
  8. ^ Abt, Helmut A.; Levato, Hugo; Grosso, Monica (July 2002), "Rotational Velocities of B Stars", The Astrophysical Journal 573 (1): 359–365, Bibcode:2002ApJ...573..359A, doi:10.1086/340590. 
  9. ^ "35 And -- Star", SIMBAD Astronomical Object Database (Centre de Données astronomiques de Strasbourg), retrieved 2012-06-22. 
  10. ^ 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. 
  11. ^ (Chinese) AEEA (Activities of Exhibition and Education in Astronomy) 天文教育資訊網 2006 年 5 月 19 日

External links[edit]