- HW Virginis
Starbox short
name = HW Virginis
constell = Virgo
ra = RA|12|44|20.2367
dec = DEC|-08|40|16.837
appmag_v =
absmag_v =
dist_ly = 1000
dist_pc = 300
class = sdB / M V
names = HIP 62157, HW Virginis
Simbad = HW+Virginis
ARICNS =HW Virginis, abbreviated HW Vir, is an
eclipsing binary system (of the Algol type) approximately 1000light-year s away (according to the fairly uncertain parallax of 3.29±2.01milliarcsecond s given by theHipparcos satellite [cite web|url=http://webviz.u-strasbg.fr/viz-bin/VizieR-5?-out.add=.&-source=I/311/hip2&recno=61949|title=HIP 62157|author=van Leeuwen, F.|work=Hipparcos, the New Reduction|year=2007|accessdate=2008-08-15] ) in theconstellation of Virgo. The system comprises an eclipsing B-type subdwarf star andred dwarf star. The two stars orbit each other every 0.116795day s. [cite journal|url=http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2000A%26A...364..199K&db_key=AST&nosetcookie=1 |title=Spectrophotometry and period analysis of the sdB eclipsing binary HW Virginis |author=Kiss, L. L.; Csák, B.; Szatmáry, K.; Furész, G.; Sziládi, K.|journal=Astronomy and Astrophysics |volume=364|pages=199 – 204|year=2000|accessdate=2008-08-15] In addition the system has a third component: an object with a mass at least 2.2% of that of the Sun (23 times that of Jupiter) orbits the system with a period of 18.8 years. This companion is likely to be abrown dwarf . [cite journal|url=http://cdsads.u-strasbg.fr/cgi-bin/nph-bib_query?2004A%26A...414.1043I&db_key=AST&nosetcookie=1|title=High-speed photometry of the pre-cataclysmic binary HW Virginis and its orbital period change|author=İbanoǧlu, C.; Çakırlı, Ö.; Taş, G.; Evren, S.|journal=Astronomy and Astrophysics |volume=414|pages=1043 – 1048|year=2004|doi=10.1051/0004-6361:20034013|accessdate=2008-08-15]References
See also
*
Algol
*CM Draconis External links
*
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