U Microscopii

Last updated
U Microscopii
Observation data
Epoch J2000       Equinox J2000
Constellation Microscopium
Right ascension 20h 29m 15.77460s [1]
Declination 40° 25 01.3084 [1]
Apparent magnitude  (V)7.0 - 14.4 [2]
Characteristics
Spectral type M5e-M7e [3]
Variable type Mira [2]
Astrometry
Radial velocity (Rv)54.00 [4]  km/s
Proper motion (μ)RA: 13.68 [1]   mas/yr
Dec.: 24.38 [1]   mas/yr
Parallax (π)1.5546 ± 0.1456 [5]   mas
Distance 2,100 ± 200  ly
(640 ± 60  pc)
Details
Luminosity 7,900 [6]   L
Temperature 2,995 [7]   K
Other designations
U  Microscopii, HIP  101063, HD  194814, CD 40°13888
Database references
SIMBAD data

U Microscopii is a Mira variable star in the constellation Microscopium. It ranges from magnitude 7 to 14.4 over a period of 334 days. [3] The Astronomical Society of Southern Africa in 2003 reported that observations of U Microscopii were very urgently needed as data on its light curve was incomplete. [8]

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References

  1. 1 2 3 4 van Leeuwen, F. (2007). "Validation of the New Hipparcos Reduction". Astronomy and Astrophysics. 474 (2): 653–64. arXiv: 0708.1752 . Bibcode:2007A&A...474..653V. doi:10.1051/0004-6361:20078357. S2CID   18759600.
  2. 1 2 Samus, N. N.; Durlevich, O. V.; et al. (2009). "VizieR Online Data Catalog: General Catalogue of Variable Stars (Samus+ 2007-2013)". VizieR On-line Data Catalog: B/GCVS. Originally Published in: 2009yCat....102025S. 1. Bibcode:2009yCat....102025S.
  3. 1 2 Watson, Christopher (4 January 2010). "U Microscopii". AAVSO Website. American Association of Variable Star Observers . Retrieved 24 March 2015.
  4. Turon, C.; Creze, M.; Egret, D.; Gomez, A.; Grenon, M.; Jahreiß, H.; Requieme, Y.; Argue, A. N.; Bec-Borsenberger, A.; Dommanget, J.; Mennessier, M. O.; Arenou, F.; Chareton, M.; Crifo, F.; Mermilliod, J. C.; Morin, D.; Nicolet, B.; Nys, O.; Prevot, L.; Rousseau, M.; Perryman, M. A. C.; et al. (1993). "Version 2 of the HIPPARCOS Input Catalogue". Bull. Inf. Cent. Donnees Astron. Strasbourg 43. 43: 5. Bibcode:1993BICDS..43....5T.
  5. Brown, A. G. A.; et al. (Gaia collaboration) (August 2018). "Gaia Data Release 2: Summary of the contents and survey properties". Astronomy & Astrophysics . 616. A1. arXiv: 1804.09365 . Bibcode: 2018A&A...616A...1G . doi: 10.1051/0004-6361/201833051 . Gaia DR2 record for this source at VizieR.
  6. Uttenthaler, S.; Lebzelter, T. (2010). "Correlation between technetium and lithium in a sample of oxygen-rich AGB variables". Astronomy and Astrophysics. 510: A62. arXiv: 0911.3507 . Bibcode:2010A&A...510A..62U. doi:10.1051/0004-6361/200912548. S2CID   119231142.
  7. McDonald, I.; Zijlstra, A. A.; Boyer, M. L. (2012). "Fundamental parameters and infrared excesses of Hipparcos stars". Monthly Notices of the Royal Astronomical Society. 427 (1): 343–357. arXiv: 1208.2037 . Bibcode:2012MNRAS.427..343M. doi:10.1111/j.1365-2966.2012.21873.x. S2CID   118665352.
  8. Cooper, Tim (2003). "Presidential address: Amateur Observations - Successes and Opportunities". Monthly Notes of the Astronomical Society of Southern Africa. 62: 234–40. Bibcode:2003MNSSA..62..234C.