Alpha Microscopii

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α Microscopii
Observation data
Epoch J2000.0      Equinox J2000.0 (ICRS)
Constellation Microscopium
Right ascension 20h 49m 58.0821s[1]
Declination −33° 46′ 47.000″[1]
Apparent magnitude (V) 4.88 to 4.94[2]
Characteristics
Spectral type G7III[1]
U−B color index +0.73[3]
B−V color index +1.00[3]
Astrometry
Radial velocity (Rv) −14.5 ± 0.9[1] km/s
Proper motion (μ) RA: 3.71[1] mas/yr
Dec.: −20.19[1] mas/yr
Parallax (π) 8.57 ± 0.80[1] mas
Distance 380 ± 40 ly
(120 ± 10 pc)
Absolute magnitude (MV) −0.45 ± 0.20[4]
Details
Mass 3.13 ± 0.18[4] M
Radius 16.4 ± 1.6[4] R
Luminosity 160[5] L
Surface gravity (log g) 2.47 ± 0.07[4] cgs
Temperature 4,923[4] K
Metallicity [Fe/H] +0.03[4] dex
Age 0.36 ± 0.07[4] Gyr
Other designations
α Mic, Alpha Microscopii, Alpha Mic, HJ 5224A, CCDM J20500-3347A, CD−34 14660, CPD−34 8799, GC 29026, HD 198232, HIP 102831, HR 7965, IDS 20437-3409 A, PPM 300665, SAO 212472, WDS 20500-3347A.[1][6]
Database references
SIMBAD data

Alpha Microscopii (Alpha Mic, α Microscopii, α Mic) is a G-type giant star in the constellation of Microscopium.[1] It has an apparent visual magnitude which varies between 4.88 and 4.94.[2]

This star has an optical visual companion, CCDM J20500-3347B, of apparent visual magnitude 10.0 approximately 20.4 arcseconds away at a position angle of 166°.[6] It has no physical connection to the star described above.[5][6]

References[edit]

  1. ^ a b c d e f g h i * alf Mic -- Star in double system, database entry, SIMBAD. Accessed on line September 4, 2008.
  2. ^ a b NSV 13329, database entry, New Catalogue of Suspected Variable Stars, the improved version, Sternberg Astronomical Institute, Moscow, Russia. Accessed on line September 4, 2008.
  3. ^ a b HR 7965, database entry, The Bright Star Catalogue, 5th Revised Ed. (Preliminary Version), D. Hoffleit and W. H. Warren, Jr., CDS ID V/50. Accessed on line September 4, 2008.
  4. ^ a b c d e f g da Silva, L. et al. (November 2006), "Basic physical parameters of a selected sample of evolved stars", Astronomy and Astrophysics 458 (2): 609–623, arXiv:astro-ph/0608160, Bibcode:2006A&A...458..609D, doi:10.1051/0004-6361:20065105 
  5. ^ a b Alpha Mic, Jim Kaler, Stars. Accessed on line September 4, 2008.
  6. ^ a b c Entry 20500-3347, The Washington Double Star Catalog, United States Naval Observatory. Accessed on line September 4, 2008.