- Description: Messier 13 is one of the brightest globular clusters visible to us in
the northern hemisphere. M13 contains hundreds of thousands of stars and is about 22 thousand
light years away. Glowing at magnitude 5.8 and about 20 arc minutes in size (2/3 the diameter
of the moon) it is visible to the naked eye from a really dark site to a more experienced observer.
Very easy to spot in binoculars! I have attempted to re-shoot this cluster several times over
the years since my first half decent shot in 1988. But, something about number 13! Every effort has
failed or had problems and this is no exception. Half-way through the planned exposure a thick
bank of forest fire smoke rolled in and blocked the sky. This is still an improvement on the
1988 shot though!
- Camera: SBIG STF-8300M at -10C
- Filters: Baader RGB
- Scope: Vixen VC200L (1800mm F9)
- Mount: Astro-Physics AP900QMD
- Exposure: 3 x 10 min per RGB channel binned 1x1
- Location: Wilson Coulee Observatory, Alberta.
- Date: September 2, 2022