GLOBULAR CLUSTER IN HERCULES
(Image Centred at ra 16h:41m / dec +36:28)
IMAGE ACQUISITION BY JIM MISTI
CLICK THE IMAGE FOR A HIGHER RESOLUTION VIEW
Misti Mountain Observatory, Arizona, USA
Type: Open Cluster
Apparent diameter: 23.2 arc minutes
Distance: 25.100 light years
Optics: Ritchey-Chretien 32" f 7.2 Telescope
CAMERA: SBIG STL 11.000
SKY CONDITIONS: Dark Skies
EXPOSURES: LRGB (14,7,7,7)
OBJECT DESCRIPTION AND IMAGE SESSION
Also called the 'Great globular cluster in Hercules', is one of the most prominent and best known globular of the Northern celestial Hemisphere. At its distance of 25,100 light years, its angular diameter, corresponds to a linear diameter of 145 light years. Visually, it is perhaps 13 arc minutes large. It contains more than 100,000 stars. The age of Messier 13 has been determined by Arp as 14 billion years, calculation he revised in 1962.
From the southern skies at its highest point it is 19 degrees above the horizon. Although images can be taken from dark locations, I choose the opportunity of processing this image coming from top notch equipment and beautiful northern skies.
Thanks Jim !!