Lacaille 9352

Lacaille 9352
Observation data
Epoch J2000      Equinox J2000
Constellation Piscis Austrinus
Right ascension 23h 05m 52.03604s[1]
Declination −35° 51′ 11.0475″[1]
Apparent magnitude (V) 7.34[2]
Characteristics
Spectral type M0.5V[3]
U−B color index +1.18[2]
B−V color index +1.50[2]
Variable type Suspected[4]
Astrometry
Radial velocity (Rv)+9.7[5] km/s
Proper motion (μ) RA: +6,768.20[1] mas/yr
Dec.: +1,327.52[1] mas/yr
Parallax (π)305.26 ± 0.70[1] mas
Distance10.68 ± 0.02 ly
(3.276 ± 0.008 pc)
Absolute magnitude (MV)9.8[6]
Details
Mass0.503 ± 0.025[3] M☉
Radius0.459 ± 0.011[3] R☉
Luminosity (bolometric)0.033[note 1] L☉
Temperature3,626[3] K
Metallicity [Fe/H]−0.22 ± 0.09[7] dex
Rotational velocity (v sin i)1[5] km/s
Other designations
HD 217987, CD -36°15693, GCTP 5584, GJ 887, LHS 70, SAO 214301, LTT 9348, LFT 1758, Cordoba 31353, NSV 14420, HIP 114046, UGPMF 591.[8]
Database references
SIMBADdata
ARICNSdata

Lacaille 9352 (Lac 9352) is a star in the southern constellation of Piscis Austrinus. With an apparent visual magnitude of 7.34,[2] this star is too faint to be viewed with the naked eye even under excellent seeing conditions. Parallax measurements place it at a distance of about 10.74 light-years (3.29 parsecs) from Earth.[1] It is the eleventh closest star system to the Solar System[9] and is the closest star in the constellation Piscis Austrinus. The ChView simulation[10] shows that its closest neighbour is the EZ Aquarii triple star system at about 4.1 ly from Lacaille 9352.

Distance

Lacaille 9352 distance estimates

Source Parallax, mas Distance, pc Distance, ly Distance, Pm Ref.
Woolley et al. (1970) 279±16 3.58+0.22
−0.19		 11.7+0.7
−0.6		 110.6+6.7
−6		 [11]
Gliese & Jahreiß (1991) 284.3±14.9 3.52+0.19
−0.18		 11.5±0.6 108.5+6
−5.4		 [12]
van Altena et al. (1995) 278.6±8.6 3.59±0.11 11.7±0.4 110.8+3.5
−3.3		 [13]
Perryman et al. (1997) (Hipparcos) 303.90±0.87 3.291±0.009 10.732±0.031 101.54±0.29 [14]
Perryman et al. (1997) (Tycho) (absents) [15]
van Leeuwen (2007) 305.26±0.70 3.276+0.008
−0.007		 10.685+0.025
−0.024		 101.08±0.23 [16]
RECONS TOP100 (2012) 305.08±0.70[note 2] 3.278±0.008 10.691+0.025
−0.024		 101.14±0.23 [17]

Non-trigonometric distance estimates are marked in italic. The most precise estimate is marked in bold.

Properties

This star has the fourth highest known proper motion,[18] (which was first noticed by Benjamin Gould in 1881[19]) moving a total of 6.9 arcseconds per year. However, this is still a very small movement overall, as there are 3,600 arcseconds in a degree of arc. The space velocity components of this star are (U, V, W) = (−93.9, −14.1, −51.4) km/s.[20] If the radial velocity (Vr) equals +9.7 km/s then about 2,700 years ago Lacaille 9352 was at its minimal distance of approximately 10.63 ly (3.26 pc) from the Sun.[21]

The spectrum of Lacaille 9352 places it at a stellar classification of M0.5V,[3] indicating it is a type of main sequence star known as a red dwarf. This was the first red dwarf star to have its angular diameter measured,[22] with the physical diameter being about 46% of the Sun's radius.[3] It has around half the mass of the Sun[3] and the outer envelope has an effective temperature of about 3,626 K.[3]

See also

Notes

  1. ↑ From L=4πR2σTeff4, where L is the luminosity, R is the radius, Teff is the effective surface temperature and σ is the Stefan–Boltzmann constant.
  2. ↑ Weighted parallax based on parallaxes from van Altena et al. (1995) and van Leeuwen (2007).

References

  1. ↑ 1.0 1.1 1.2 1.3 1.4 1.5 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. ↑ 2.0 2.1 2.2 2.3 Cousins, A. W. J. (1973). "UBV photometry of some southern stars". Monthly Notes of the Astronomical Society of Southern Africa 32: 11. Bibcode:1973MNSSA..32...11C.
  3. ↑ 3.0 3.1 3.2 3.3 3.4 3.5 3.6 3.7 Demory, B.-O. et al. (October 2009), "Mass-radius relation of low and very low-mass stars revisited with the VLTI", Astronomy and Astrophysics 505 (1): 205–215, arXiv:0906.0602, Bibcode:2009A&A...505..205D, doi:10.1051/0004-6361/200911976
  4. ↑ Micela, G.; Pye, J.; Sciortino, S. (April 1997). "Coronal properties of nearby old disk and halo dM stars". Astronomy and Astrophysics 320: 865–877. Bibcode:1997A&A...320..865M.
  5. ↑ 5.0 5.1 Torres, C. A. O. (December 2006). "Search for associations containing young stars (SACY). I. Sample and searching method". Astronomy and Astrophysics 460 (3): 695–708. arXiv:astro-ph/0609258. Bibcode:2006A&A...460..695T. doi:10.1051/0004-6361:20065602.
  6. ↑ Murdin, Paul, ed. (November 2000). "Lacaille 9352". Encyclopedia of Astronomy and Astrophysics (in English). Bristol: Institute of Physics Publishing. Bibcode:2000eaa..bookE5158. doi:10.1888/0333750888/5158. ISBN 0333750888. absolute magnitude is 9.8
  7. ↑ López-Morales, Mercedes (May 2007). "On the Correlation between the Magnetic Activity Levels, Metallicities, and Radii of Low-Mass Stars". The Astrophysical Journal 660 (1): 732–739. arXiv:astro-ph/0701702. Bibcode:2007ApJ...660..732L. doi:10.1086/513142.
  8. ↑ "LACAILLE 9352 -- Pre-main sequence Star". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2010-01-20.
  9. ↑ Research Consortium on Nearby Stars. "The One Hundred Nearest Star Systems". Georgia State University. Retrieved 2010-01-20.
  10. ↑ "Solstation and ChView". Retrieved 2010-04-20.
  11. ↑ Woolley R.; Epps E. A.; Penston M. J.; Pocock S. B. (1970). "Woolley 887". Catalogue of stars within 25 parsecs of the Sun. Retrieved 2014-10-20.
  12. ↑ Gliese, W. and Jahreiß, H. (1991). "Gl 887". Preliminary Version of the Third Catalogue of Nearby Stars. Retrieved 2014-10-20.
  13. ↑ Van Altena W. F., Lee J. T., Hoffleit E. D. (1995). "GCTP 5584". The General Catalogue of Trigonometric Stellar Parallaxes (Fourth ed.). Retrieved 2014-10-20.
  14. ↑ Perryman et al. (1997). "HIP 114046". The Hipparcos and Tycho Catalogues. Retrieved 2014-10-20.
  15. ↑ Perryman et al. (1997). "HIP 114046". The Hipparcos and Tycho Catalogues. Retrieved 2014-10-20.
  16. ↑ van Leeuwen F. (2007). "HIP 114046". Validation of the new Hipparcos reduction. Retrieved 2014-10-20.
  17. ↑ "RECONS TOP100". THE ONE HUNDRED NEAREST STAR SYSTEMS brought to you by RECONS (Research Consortium On Nearby Stars). 2012. Retrieved 2014-10-20.
  18. ↑ "High Proper Motion Stars in the Hipparcos Catalogue". European Space Agency. July 1, 2007. Retrieved 2010-01-20.
  19. ↑ Gould, B. A. (1881). "Corrigenda in the Uranometria Argentina. Star with large proper motion". Astronomische Nachrichten 100: 7–10. Bibcode:1881AN....100....7G. doi:10.1002/asna.18811000104.
  20. ↑ "ARICNS star page of Lacaille 9352". Astronomisches Rechen-Institut Heidelberg. Retrieved 2010-04-16.
  21. ↑ "Annotations on NAME LACAILLE 9352 object". SIMBAD. Centre de Données astronomiques de Strasbourg. Retrieved 2010-04-16.
  22. ↑ Glindemann, Andreas; Paresce, Francesco. "Giant Eyes for the VLT Interferometer". European Southern Observatory. Retrieved 2010-01-20.

External links