[vsnet-alert 10609] Omega CMa outburst

[Sebastian Otero]

Omega CMa is in outburst at V= 3.8.

The star shows two kind of events."Mini-outbursts" lasting 2-3 weeks and with amplitudes less than 0.15 mag. and huge events every 7-9 years (lasting 3 years or so).

The current bright state is already 0.4 mag. above the quiescent level from last season (V= 4.1-4.2) implying this is one of the huge events and it is barely starting.

There has been spectroscopic confirmation from Brazilian observers using the FEROS instrument at La Silla (October 20).

A lightcurve since 1975 from several sources, showing the major events:
http://ar.geocities.com/varsao/omeCMa_HOY.gif

See that the last event got to V= 3.55 or so at its peak so the star will probably continue to brighten over the next months.
Chart at:
http://ar.geocities.com/varsao/Carta_ome_CMa.htm
(Forget about that 34.675 d. period, I have to update the chart...)

Best wishes,
Sebastian.