"Great Cluster in Hercules" M13

Object Information:

In 1716, English astronomer Edmond Halley noted, "This is but a little Patch, but it shews itself to the naked Eye, when the Sky is serene and the Moon absent." Of course, M13 is now modestly recognized as the Great Globular Cluster in Hercules, one of the brightest globular star clusters in the northern sky. Telescopic views reveal the spectacular cluster's hundreds of thousands of stars. At a distance of 25,000 light-years, the cluster stars crowd into a region 150 light-years in diameter, but approaching the cluster core upwards of 100 stars could be contained in a cube just 3 light-years on a side. For comparison, the closest star to the Sun is over 4 light-years away. Along with the cluster's dense core, the outer reaches of M13 are highlighted in thissharp color image. The cluster's evolved red and blue giant stars show up in yellowish and blue tints.

More information here.

Exposure Information: 27,5 minutes exposure

Lights: 55x30" 1600ISO
Darks: 0
Flats: 30
Bias: 50

Sensor temperature 21ºC
Moon phase 12%

Note: No guiding. My first image of a globular cluster!
Imaged at: Prades, Tarragona, CATALUNYA - SPAIN
Equipment: Optics - GSO- 200/1000 Newtonian f/5
Camera - Canon 450D moded (IR filter removed)
Mount - Sky-Watcher Neq6 PROII
Image date: July 02, 2016