Friday, 15 January 2010

V838 Monocerotis

V838 Mon is a star that went extremely bright for a few days in early 2002. Usually 16th magnitude, it reached 6.75 magnitude. At a distance of > 6 kpc this made it temporarily the brightest star in the Milky Way. Astronomers noticed a few days after it had faded that there was a brightening in the infrared. It turned out this was a light echo from the surrounding interstellar matter. You can google 'light echo' or 'V838 Mon' and you may well be familiar with the set of Hubble pictures, taken during successive months. Well, I thought I would try and hunt it down and see how it was doing. Not a lot. Never mind. That's mostly what happens in the universe.


Tomasz said...

if the V838 Mon images were taken with standard filters and you are not going to publish them individually, I recommend sending the photometric measurement to Vitaly Goranskij, who puts all the available data for the star at a web page; see

Tomas (tomkam)

Dr Dan said...

Thanks very much Tomas. I have not had any success doing photometry on my images, because I took the sub-frames in jpeg mode on a Canon EOS 350D. The filters are not standard and magnitude estimates are usually out by 1 or more mag! If I ever get to use a proper CCD like an Atik on the 20" scope I will send it to Vitaly. Maybe this winter???