Friday, August 26, 2011

AM August 26th - V594 Cassiopeiae dimming event!

  Last night I had some of the clearest skies all summer and made 14 variable star estimates. One star I've been watching since last summer is V594 Cassiopeiae. It's a YSO (Young Stellar Object) just off to the side of a nice little star cluster called NGC 225 in Cassiopeia. All the time I've set the telescope on it, it hasn't done much. I've seen it as bright as 10.3 magnitude and as dim as 10.5 magnitude, so I couldn't call it an exciting target. Well, last night I finally saw a dimming event down to 10.8 magnitude. It isn't much, but it's the most activity I've seen. YSO stars are my favorite because they are unpredictable and under-observed. They're thought to be still condensing out of nebulae and surrounded by gas and dust. So last night what probably happened was a thick part of the gas and dust shell orbited into a spot between Earth and the star, and caused the dimming.