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Xi Telescopii

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Xi Telescopii

A light curve for Xi Telescopii, plotted from Hipparcos data[1]
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Telescopium
Right ascension 20h 07m 23.15599s[2]
Declination −52° 52′ 50.8490″[2]
Apparent magnitude (V) 4.95[3] (+4.89 – 4.94)[4]
Characteristics
Spectral type K5 III[5] or M1 IIab[6]
U−B color index +1.90[3]
B−V color index +1.61[3]
Variable type LB:[4]
Astrometry
Radial velocity (Rv)+36.0[7] km/s
Proper motion (μ) RA: −12.98[2] mas/yr
Dec.: +7.50[2] mas/yr
Parallax (π)3.02 ± 0.35 mas[2]
Distanceapprox. 1,100 ly
(approx. 330 pc)
Absolute magnitude (MV)−2.64[8]
Details
Radius56[9] R
Luminosity2,973[10] L
Temperature4,030[10] K
Other designations
ξ Tel, CPD−53°9794, FK5 755, HD 190421, HIP 99120, HR 7673, SAO 246443[11]
Database references
SIMBADdata

Xi Telescopii, Latinized from ξ Telescopii, is a solitary[6] star in the southern constellation of Telescopium.[11] It is visible to the naked eye, with an apparent visual magnitude of +4.95.[3] Based upon an annual parallax shift of 3.02 mas as measured from Earth,[2] it is located approximately 1,100 light-years from the Sun.

This is an evolved star with a stellar classification of K5 III[5] or M1 IIab,[6] indicating it is a giant or bright giant star. This is a variable star tentatively classified as a slow irregular-type variable with a brightness that varies between magnitude +4.89 and +4.94.[4] Koen and Eyer examined the Hipparcos data for this star, and found that it varied periodically, with a period of 12.36 days, and an amplitude of 0.0083 magnitudes.[12] With around 56[9] times the Sun's radius, it shines with a luminosity approximately 2,973 times that of the Sun and has a surface temperature of 4,030 K.[10]

References

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  1. ^ "/ftp/cats/more/HIP/cdroms/cats", Centre de Données astronomiques de Strasbourg, Strasbourg astronomical Data Center, retrieved 15 October 2022.
  2. ^ a b c d e f van Leeuwen, F. (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, S2CID 18759600.
  3. ^ a b c d Fernie, J. D. (May 1983), "New UBVRI photometry for 900 supergiants", Astrophysical Journal Supplement Series, 52: 7–22, Bibcode:1983ApJS...52....7F, doi:10.1086/190856.
  4. ^ a b c Watson, Christopher (May 3, 2013). "NSV 12783". AAVSO Website. American Association of Variable Star Observers. Retrieved 2017-06-03.
  5. ^ a b Houk, Nancy; Cowley, A. P. (1978), Michigan catalogue of two-dimensional spectral types for the HD stars, vol. 1, Ann Arbor: Dept. of Astronomy, University of Michigan, Bibcode:1975mcts.book.....H.
  6. ^ a b c 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, arXiv:0806.2878, Bibcode:2008MNRAS.389..869E, doi:10.1111/j.1365-2966.2008.13596.x, S2CID 14878976.
  7. ^ Wielen, R.; et al. (2000), "Sixth Catalogue of Fundamental Stars (FK6). Part III. Additional fundamental stars with direct solutions", Veröffentlichungen Astronomisches Rechen-Institut Heidelberg, vol. 37, no. 37, Karlsruhe: Verlag G. Braun, pp. 1–308, Bibcode:2000VeARI..37....1W, ISBN 3-7650-0536-3.
  8. ^ Anderson, E.; Francis, Ch. (2012), "XHIP: An extended hipparcos compilation", Astronomy Letters, 38 (5): 331, arXiv:1108.4971, Bibcode:2012AstL...38..331A, doi:10.1134/S1063773712050015, S2CID 119257644.
  9. ^ a b Pasinetti Fracassini, L. E.; et al. (2001), "Catalogue of Apparent Diameters and Absolute Radii of Stars (CADARS)", Astronomy & Astrophysics, 367 (3rd ed.): 521–24, arXiv:astro-ph/0012289, Bibcode:2001A&A...367..521P, doi:10.1051/0004-6361:20000451, S2CID 425754.
  10. ^ a b c McDonald, I.; et al. (2012), "Fundamental Parameters and Infrared Excesses of Hipparcos Stars", Monthly Notices of the Royal Astronomical Society, 427 (1): 343–57, arXiv:1208.2037, Bibcode:2012MNRAS.427..343M, doi:10.1111/j.1365-2966.2012.21873.x, S2CID 118665352.
  11. ^ a b "ksi Tel". SIMBAD. Centre de données astronomiques de Strasbourg. Retrieved 2017-06-01.
  12. ^ Koen, Chris; Eyer, Laurent (March 2002). "New periodic variables from the Hipparcos epoch photometry". Monthly Notices of the Royal Astronomical Society. 331 (1): 45–59. arXiv:astro-ph/0112194. Bibcode:2002MNRAS.331...45K. doi:10.1046/j.1365-8711.2002.05150.x.