21 Leonis Minoris Explained

21 Leonis Minoris is a star in the constellation of Leo Minor. With an apparent magnitude of about 4.5, the star is faintly visible to the naked eye (see Bortle scale). Parallax estimates made by the Hipparcos spacecraft put it at a fairly close distance of about 92.1abbr=offNaNabbr=off away from the Earth. It is considered a member of the Sirius supercluster.

21 Leonis Minoris rotates fairly fast for a star; its projected rotational velocity is estimated to be 155 km/s so it must be rotating at least that fast. It has been listed as a fast-rotating spectral standard star for the spectral type of A7V, as opposed to the slow-rotating standard star 2 Hydrae.[1] It is also a Delta Scuti variable, and its apparent magnitude varies from 4.47 to 4.52.[2]

21 Leonis Minoris has an infrared excess, suggesting a debris disk around it. The black body fit has a temperature of with an orbital radius of .

Notes and References

  1. 1989ApJS...70..623G. 10.1086/191349. The late A-type stars - Refined MK classification, confrontation with Stromgren photometry, and the effects of rotation. The Astrophysical Journal Supplement Series. 70. 623. 1989. Gray. R. O.. Garrison. R. F.. free.
  2. 2009yCat....102025S. 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. etal. Samus, N. N.. Durlevich, O. V.. 2009.