U Microscopii

U Microscopii

The visual band light curve of U Microscopii, from AAVSO data[1]
Observation data Epoch J2000      Equinox J2000
Constellation	Microscopium
Right ascension	20^h 29^m 15.77460^s[2]
Declination	−40° 25′ 01.3084″[2]
Apparent magnitude (V)	7.0 - 14.4 [3]
Characteristics
Spectral type	M5e-M7e[4]
Variable type	Mira[3]
Astrometry
Radial velocity (Rv)	−54.00[5] km/s
Proper motion (μ)	RA: −13.68[2] mas/yr Dec.: −24.38[2] mas/yr
Parallax (π)	1.5546±0.1456 mas[6]
Distance	2,100 ± 200 ly (640 ± 60 pc)
Details
Luminosity	7,900[7] L☉
Temperature	2,995[8] 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.^[4] 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.^[9]

References

1. "Download Data". aavso.org. AAVSO. Retrieved 1 October 2021.
2. 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.
3. 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.
4. Watson, Christopher (4 January 2010). "U Microscopii". AAVSO Website. American Association of Variable Star Observers. Retrieved 24 March 2015.
5. 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.
6. 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.
7. 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.
8. 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.
9. 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.