Astronomy:19 Arietis

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Short description: Star in the constellation Aries
19 Arietis
Observation data
Equinox J2000.0]] (ICRS)
Constellation Aries
Right ascension  02h 13m 03.30440s[1]
Declination +15° 16′ 47.5005″[1]
Apparent magnitude (V) 5.70[2]
Characteristics
Spectral type M0 III[3]
U−B color index +1.95[2]
B−V color index +1.55[2]
R−I color index 0.97
Variable type Semiregular[4]
Astrometry
Radial velocity (Rv)21.11 ± 0.26[5] km/s
Proper motion (μ) RA: +97.95[1] mas/yr
Dec.: -20.30[1] mas/yr
Parallax (π)6.81 ± 0.38[1] mas
Distance480 ± 30 ly
(147 ± 8 pc)
Details
Radius39[6] R
Temperature3,690[7] K
Metallicity [Fe/H]–0.02 ± 0.11[8] dex
Other designations
BD+14 357, FK5 1057, HD 13596, HIP 10328, HR 648, SAO 92841.[9]
Database references
SIMBADdata

19 Arietis (abbreviated 19 Ari) is a star in the northern constellation of Aries. 19 Arietis is the Flamsteed designation. It has an apparent visual magnitude of 5.70,[2] which means it is faintly visible to the naked eye. Based upon an annual parallax shift of 6.81 mas,[1] it is approximately 480 light-years (150 parsecs) away from Earth. At that distance, the brightness of the star is diminished by 0.21 in magnitude from extinction caused by interstellar gas and dust.[5]

This is a red giant star with a stellar classification of M0 III.[3] It is a semi-regular variable with periods of 32 and 275 days; the brightness of the star changes by an amplitude of 0.14 in magnitude during those intervals.[4] The measured angular diameter of this star, after correction for limb darkening, is 2.44 ± 0.03 mas.[10] At the estimated distance of Delta Ophiuchi,[1] this yields a physical size of about 39 times the radius of the Sun.[6] The effective temperature of the outer envelope is 3,690 K,[7] giving it the cool reddish glow of an M-type star.[11]

References

  1. 1.0 1.1 1.2 1.3 1.4 1.5 1.6 van Leeuwen, F. (November 2007), "Validation of the new Hipparcos reduction", Astronomy and Astrophysics 474 (2): 653–664, doi:10.1051/0004-6361:20078357, Bibcode2007A&A...474..653V. 
  2. 2.0 2.1 2.2 2.3 Johnson, H. L. et al. (1966), "UBVRIJKL photometry of the bright stars", Communications of the Lunar and Planetary Laboratory 4 (99): 99, Bibcode1966CoLPL...4...99J. 
  3. 3.0 3.1 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. 
  4. 4.0 4.1 Yeşilyaprak, C.; Aslan, Z. (2007), "Period-luminosity relation for M-type semiregular variables from Hipparcos parallaxes", Monthly Notices of the Royal Astronomical Society 355 (2): 601–607, doi:10.1111/j.1365-2966.2004.08344.x, Bibcode2004MNRAS.355..601Y. 
  5. 5.0 5.1 Famaey, B. et al. (January 2005), "Local kinematics of K and M giants from CORAVEL/Hipparcos/Tycho-2 data. Revisiting the concept of superclusters", Astronomy and Astrophysics 430 (1): 165–186, doi:10.1051/0004-6361:20041272, Bibcode2005A&A...430..165F. 
  6. 6.0 6.1 Lang, Kenneth R. (2006), Astrophysical formulae, Astronomy and astrophysics library, 1 (3rd ed.), Birkhäuser, ISBN 3-540-29692-1, https://books.google.com/books?id=OvTjLcQ4MCQC&pg=PA41. . The radius (R*) is given by:
    [math]\displaystyle{ \begin{align} 2\cdot R_* & = \frac{(147\cdot 2.44\cdot 10^{-3})\ \text{AU}}{0.0046491\ \text{AU}/R_{\bigodot}} \\ & \approx 77.2\cdot R_{\bigodot} \end{align} }[/math]
  7. 7.0 7.1 Wittkowski, M. et al. (December 2006), "Tests of stellar model atmospheres by optical interferometry. IV. VINCI interferometry and UVES spectroscopy of Menkar", Astronomy and Astrophysics 460 (3): 855–864, doi:10.1051/0004-6361:20066032, Bibcode2006A&A...460..855W. 
  8. Taylor, B. J. (February 1999), "Catalogs of temperatures and [Fe/H] averages for evolved G and K stars", Astronomy and Astrophysics Supplement 134 (3): 523–524, doi:10.1051/aas:1999153, Bibcode1999A&AS..134..523T. 
  9. "19 Ari". SIMBAD. Centre de données astronomiques de Strasbourg. http://simbad.u-strasbg.fr/simbad/sim-basic?Ident=19+Ari. 
  10. Richichi, A.; Percheron, I.; Khristoforova, M. (February 2005), "CHARM2: An updated Catalog of High Angular Resolution Measurements", Astronomy and Astrophysics 431 (2): 773–777, doi:10.1051/0004-6361:20042039, Bibcode2005A&A...431..773R. 
  11. "The Colour of Stars", Australia Telescope, Outreach and Education (Commonwealth Scientific and Industrial Research Organisation), December 21, 2004, archived from the original on March 18, 2012, https://web.archive.org/web/20120318151427/http://outreach.atnf.csiro.au/education/senior/astrophysics/photometry_colour.html, retrieved 2012-01-16 

External links