Astronomy:Nu Fornacis

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Short description: Bluish variable star in the constellation Fornax
Nu Fornacis
NuForLightCurve.png
A light curve for Nu Fornacis plotted from TESS data[1]
Observation data
Equinox J2000.0]] (ICRS)
Constellation Fornax
Right ascension  02h 04m 29.43861s[2]
Declination −29° 17′ 48.5477″[2]
Apparent magnitude (V) 4.69[3] (4.68 – 4.73[4])
Characteristics
Spectral type B9.5IIIspSi[5]
U−B color index −0.51[3]
B−V color index −0.17[3]
Variable type α2 CVn[6]
Astrometry
Radial velocity (Rv)+18.50[7] km/s
Proper motion (μ) RA: +12.79[8] mas/yr
Dec.: +8.48[8] mas/yr
Parallax (π)8.79 ± 0.26[2] mas
Distance370 ± 10 ly
(114 ± 3 pc)
Absolute magnitude (MV)−0.60[9]
Details
Mass3.65±0.18[10] M
Radius3.44[11] R
Luminosity245[10] L
Temperature13,400[12] K
Rotation1.89[12] d
Rotational velocity (v sin i)50±5[12] km/s
Other designations
ν For, CD−29°706, FK5 1055, GC 2506, HD 12767, HIP 9677, HR 612, SAO 167532[8]
Database references
SIMBADdata

Nu Fornacis, Latinized from ν Fornacis, is a single,[13] variable star in the southern constellation of Fornax. It is blue-white in hue and faintly visible to the naked eye with an apparent visual magnitude that fluctuates around 4.69.[3] This body is located approximately 370 light years distant from the Sun based on parallax,[2] and is drifting further away with a radial velocity of +18.5 km/s.[7] It is a candidate member of the Pisces-Eridanus stellar stream, which suggests an age of 120 million years or less.[14]

This object is an Ap star[15] with a stellar classification of B9.5IIIspSi[5] matching a late B-type giant star. The 'Si' suffix indicates an abundance anomaly of silicon. It is an Alpha2 Canum Venaticorum variable that ranges from magnitude 4.68 down to 4.73 with a period of 1.89 days – the same as its rotational period.[6][12] It is 3.65 times as massive and 245 times as luminous as the Sun,[10] with 3.44 times the Sun's diameter.[11]

References

  1. "MAST: Barbara A. Mikulski Archive for Space Telescopes". Space Telescope Science Institute. https://mast.stsci.edu/portal/Mashup/Clients/Mast/Portal.html. 
  2. 2.0 2.1 2.2 2.3 van Leeuwen, F. (2007). "Validation of the new Hipparcos reduction". Astronomy and Astrophysics 474 (2): 653–664. doi:10.1051/0004-6361:20078357. Bibcode2007A&A...474..653V. http://www.aanda.org/articles/aa/full/2007/41/aa8357-07/aa8357-07.html.  Vizier catalog entry
  3. 3.0 3.1 3.2 3.3 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. Bibcode2002yCat.2237....0D. 
  4. Samus, N. N. et al. (2009). "General Catalogue of Variable Stars". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S 1. Bibcode2009yCat....102025S. 
  5. 5.0 5.1 Abt, Helmut A.; Morrell, Nidia I. (July 1995). "The relation between Rotational Velocities and Spectral Peculiarities among A-type stars". The Astrophysical Journal Supplement Series 99: 135–172. doi:10.1086/192182. Bibcode1995ApJS...99..135A. 
  6. 6.0 6.1 Samus, N. N. et al. (2017). "General Catalogue of Variable Stars". Astronomy Reports. 5.1 61 (1): 80–88. doi:10.1134/S1063772917010085. Bibcode2017ARep...61...80S. 
  7. 7.0 7.1 Wilson, R. E. (1953). "General Catalogue of Stellar Radial Velocities". Washington (Carnegie Institution of Washington). Bibcode1953GCRV..C......0W. 
  8. 8.0 8.1 8.2 "* nu. For". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=%2A+nu.+For. 
  9. Anderson, E.; Francis, Ch. (2012). "XHIP: An extended hipparcos compilation". Astronomy Letters 38 (5): 331. doi:10.1134/S1063773712050015. Bibcode2012AstL...38..331A. 
  10. 10.0 10.1 10.2 North, P. (1998). "Do SI stars undergo any rotational braking?". Astronomy and Astrophysics 334: 181–87. Bibcode1998A&A...334..181N. 
  11. 11.0 11.1 Shulyak, D. et al. (2014). "Interferometry of chemically peculiar stars: Theoretical predictions versus modern observing facilities". Monthly Notices of the Royal Astronomical Society 443 (2): 1629. doi:10.1093/mnras/stu1259. Bibcode2014MNRAS.443.1629S. 
  12. 12.0 12.1 12.2 12.3 Leone, F. et al. (2000). "A spectroscopic study of the magnetic chemically peculiar star nu Fornacis". Astronomy and Astrophysics 359: 635–38. Bibcode2000A&A...359..635L. 
  13. 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. doi:10.1111/j.1365-2966.2008.13596.x. Bibcode2008MNRAS.389..869E. 
  14. Curtis, Jason L. et al. (August 2019). "TESS Reveals that the Nearby Pisces─Eridanus Stellar Stream is only 120 Myr Old". The Astronomical Journal 158 (2): 11. doi:10.3847/1538-3881/ab2899. 77. Bibcode2019AJ....158...77C. 
  15. Chen, P. S. et al. (May 2017). "A New Photometric Study of Ap and Am Stars in the Infrared". The Astronomical Journal 153 (5): 28. doi:10.3847/1538-3881/aa679a. 218. Bibcode2017AJ....153..218C.