NGC 7789 (Caroline’s Rose Cluster) is a class II 2 r open cluster located approximately 7,600 light-years away in Cassiopeia. The cluster was discovered by Caroline Herschel in 1783.
To make this image, I used binned RGB data taken in July, 2013 along with luminance data taken last night.
Luminance – 12x600s – 120 minutes – binned 1x1
RGB – 8x300s – 40 minutes each – binned 2x2
240 minutes total exposure – 4 hours
Imaged from Dardenne Prairie, Missouri (a red zone) on July 16th, 2013 and October 6th, 2016 with a SBIG ST-8300M on an Astro-Tech AT90DT at f/6.7 603mm.
LRGB - https://www.flickr.com/photos/dcrowson/30137145136/sizes/l