HR 3803

(Redirected from HD 82668)
HR 3803
Observation data
Epoch J2000      Equinox J2000
Constellation Vela
Right ascension 09h 31m 13.31891s[1]
Declination –57° 02′ 03.7578″[1]
Apparent magnitude (V) 3.16[2]
Characteristics
Spectral type K5 III[3]
U−B color index +1.88[4]
B−V color index +1.55[4]
Astrometry
Proper motion (μ) RA: –32.54[1] mas/yr
Dec.: +5.87[1] mas/yr
Parallax (π) 13.65 ± 0.10[1] mas
Distance 239 ± 2 ly
(73.3 ± 0.5 pc)
Details
Mass 2.0[5] M
Temperature 3,860[5] K
Other designations
N Velorum, N Vel, CP–56 2270, HD 82668, FK5 361, HIP 46701, HR 3803, SAO 237067.

HR 3803 or N Velorum (N Vel) is a 3rd-magnitude star on the border between the southern constellations Carina and Vela. Based upon parallax measurements, it is approximately 239 light-years (73 parsecs) from Earth. It is an orange-hued K-type giant star and has twice the mass of the Sun.[5] The measured angular diameter of this star, after correction for limb darkening, is 7.13 ± 0.08 mas.[7] At the estimated distance of Eta Draconis,[1] this yields a physical size of about 29 times the radius of the Sun.[6]

In 1752, French astronomer Nicolas Louis de Lacaille divided the former constellation Argo Navis into three separate constellations, and then referenced its stars by extending Bayer's system of star nomenclature;[8] this star was given the designation N Velorum. In 1871 Benjamin Apthorp Gould discovered this star to be variable, but this occurred prior to the standardization of variable star nomenclature by German astronomer Friedrich Wilhelm Argelander during the nineteenth century, so it does not fall into the standard range of variable star designations.[9]

The star should not be confused with n Velorum.

References

1. 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 Wielen, R. et al. (1999), Sixth Catalogue of Fundamental Stars (FK6). Part I. Basic fundamental stars with direct solutions (35), Astronomisches Rechen-Institut Heidelberg, Bibcode:1999VeARI..35....1W
3. ^ Morgan, W. W.; Keenan, P. C. (1973). "Spectral Classification". Annual Review of Astronomy and Astrophysics 11 (1): 29. Bibcode:1973ARA&A..11...29M. doi:10.1146/annurev.aa.11.090173.000333.
4. ^ a b Johnson, H. L. et al. (1966). "UBVRIJKL photometry of the bright stars". Communications of the Lunar and Planetary Laboratory 4 (99). Bibcode:1966CoLPL...4...99J.
5. ^ a b c Gondoin, P. (December 1999), "Evolution of X-ray activity and rotation on G-K giants", Astronomy and Astrophysics 352: 217–227, Bibcode:1999A&A...352..217G
6. ^ a b Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library 1 (3 ed.), Birkhäuser, ISBN 3540296921. The radius (R*) is given by:
\begin{align} 2\cdot R_* & = \frac{(73.3\cdot 3.72\cdot 10^{-3})\ \text{AU}}{0.0046491\ \text{AU}/R_{\bigodot}} \\ & \approx 58.7\cdot R_{\bigodot} \end{align}
7. ^ Richichi; Percheron, I.; Khristoforova, M. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics 431: 773–777, Bibcode:2005A&A...431..773R, doi:10.1051/0004-6361:20042039
8. ^ http://homepage.mac.com/andjames/Page206.htm
9. ^ Hoffleit, Dorrit (December 1987), "History of Variable Star Nomenclature", The Journal of the American Association of Variable Star Observers 16 (2): 65–70, Bibcode:1987JAVSO..16...65H, retrieved 2012-02-02