- Description: M23 is a large, bright open cluster in Sagittarius. Measuring 27
arc minutes across makes it about the size of the full moon, 150 stars with a total magnitude
of about 5.5. In other words, visible to the naked eye from good skies or with a pair of binoculars.
Blue exposures cut short by the cluster descending into a cloud bank.
- Camera: SBIG STF-8300M at -15C
- Filter: Baader RGB
- Scope: Takahashi FSQ-106N
- Exposure: 3x10 minutes red, 3x10 green, 2x10 blue.
- Location: 5th Meridian Observatory grounds, near Cayley AB.
- Date: August 18, 2012