M 12

About image 

Messier 12 (NGC 6218) is a globular cluster in the constellation of Ophiuchus.
It is about 16,400 light-years from Earth and has a diameter of about 75 light-years: its brightest stars are of 12th magnitude.
It is rather loosely packed for a globular and was once thought to be a tightly concentrated open cluster 

[text adapted from Wikipedia].
It is nice to see through the cluster’s stars those two faint galaxies (catalogued as PCG 1103219).

Technical data
Optic         GSO RC12 Truss - Aperture 304mm, focal lenght 2432mm, f/8
Mount       10Micron GM2000 HPSII
Camera        ZWO ASI 2600 MM Pro with filter wheel 7 positions
Filters        Astrodon Gen2 E-Serie Tru-Balance 50mm unmounted RGB  
Guiding system   ZWO OAG-L with guide camera ASI 174MM Mini
Exposure details   L 30x120" bin3 -15C 

         R 13x120" bin3 -15C
            G 14x120" bin3 -15C
         B 12x120" bin3 -15C
Total integration  2h18'
Acquisition      Voyager, PHD2
Processing      Pixinsight 1.8, Photoshop CS5, NoiseXTerminator
SQM-L       21.00    
Location       Promiod (Aosta Valley, Italy), own remote observatory
Date           27 May/26 June 2023


© Roberto Marinoni 2019 - All rights reserved