This news comes in a little late, however hopefully still in time to make some follow-up measurements.
On the night of 19th and 21st June, 2012, I was attempting to image Pluto. While I compare it with DSS image to locate Pluto, I was able to make my first (accidental) celestial discovery (first amateur discovery from India in all likelihood, and no doubt Her first CCD discovery, which has also been the quickest - at just the 21st day of usage since its purchase 6 months ago). I thought its a bright nova due to inexperience in the field of variable stars. I have been a very active visual DSO observer and visual comet chaser for past few years.
Placed just 1 arc minute away from Pluto, I was astonished to see such a bright new "Nova" which I visually estimated at ~11.5 mag. I did also check with AAVSO chart plotter but didnt see anything at the source position. I contacted a virtual friend of mine, the legendary Dr. Alan Hale (of comet Hale Bopp fame) and he was able to quickly make a visual estimate at 13.5 mag on 23rd night. I shot an email to CBAT on 23rd June, awaiting them to put it up on their TOCP page as a new Nova candidate. However after an aggreviating wait of few days I got to see something by them; it turns out to be a "previously unreported Mira variable star". The reason why it appears bright in my image is it was taken unfiltered, as it was a routine imaging session. The background source is ~17th magnitude IRAS 18322-1921. The coordinates of this object are - RA 18* 35' 10" / DEC -19* 19' 31".
Coincidentally the bright new Nova was discovered just 10 degrees away from my object on 26th of June!
I sincerely hope the variable star experts here can make follow up measurements of this source, which still should be quite bright. I havent taken an image after 23rd June, since this part of south India is notorious for being clouded most year round, pre and post monsoons.
Note: Do excuse me. Being a newbie to this specific field (and active in other areas of amateur astronomy), I am not sure should I be calling my accidental discovery as a Mira "type" star discovery, or new Mira star discovery itself.
Is any new discovery classified as a Mira star, or a Mira type based on its progenitor. Thanks for clarifying.
Amar A. Sharma
off Bangalore, India
+12* 36' / 77E 43'