[Aavso-photometry] V581 CrA

[Patrick Wils]

V581 CrA is classified in the GCVS as a Mira star with a period of 1100: days.  A quick look at the recent ASAS light curve <http://www.astrouw.edu.pl/cgi-asas/asas_variable/182443-4524.7,asas3,0,0,500,0,0> shows no sign of this periodicity and not even of Mira-like behavior.  It's a very red star (2MASS J-Ks=2.07) and its amplitude is very large: more than 5 magnitudes in the ASAS V data with a maximum around mag 10, while USNO-B1.0 has a blue magnitude of 13.5 in 1974 (and likely in red it was much brighter) and a red magnitude of 18.4 in 1985.  

The ASAS data indicate that V581 CrA is faint again at the moment.  It would be interesting to see how faint it actually is now, and follow it on its rise, whenever that may be, to learn more about this intriguing variable.

Patrick