The Great Globular Cluster in Hercules in its splendor
The Great Globular Cluster in Hercules in its splendor
I decided to image the Great Globular Cluster in Hercules (M13) despite the presence of the bright Moon. In this article I would like to share the result of this effort, which is my best capture of M13 to date.
The sky was clear and seeing and transparency were above average. I couldn’t miss this opportunity and decided to give a try. I imaged Messier 13, the Great Globular Cluster in Hercules.
Messier 13 shines as the most remarkable globular cluster visible in the Northern Hemisphere. Situated 25,000 light years away from us, this celestial gem stretches across 145 light years and has an estimated population of 300,000 stars.
Now imagine how the sky would appear from an hypothetical planet orbiting one of the stars near the center of Messier 13. The distance from our hypothetical planet to the closest star would be about 0.05 light-year. For comparison, in our solar system, this would be inside the Oort Cloud!
Across the entire sky, inhabitants of this hypothetical planet would see 10,000 stars brighter than 1st magnitude, and more than a thousand brighter than Sirius!
Setup
Location: my driveway in Richmond Hill (ON)
Scope: C8 SCT
Mount: Celestron AVX
Guiding camera: ZWO ASI224MC, IR-Cut filter, PHD2
Guide Scope: Orion Deluxe Mini 50mm Guide Scope
Total integration time: 60 minutes (30×120 seconds).
Calibration frames: 10 dark, 15 flat, 100 bias
Size: 29.7 x 29.7 arcmin
Radius: 0.350 deg
Pixel scale: 0.592 arcsec/pixel
Note: Scroll the slider to switch between the images of Messier 13 and the galaxy IC 4617 (highlighted in red) with and without annotations.
I would like to conclude this post with a curiosity. In 1974, the Arecibo Radio Telescope in Puerto Rico sent a message towards Messier 13. The message, conceived by a team of scientists led by Frank Drake, aimed to communicate our presence and intelligence to potential extraterrestrial civilizations. Comprising a pictorial representation of our fundamental knowledge, the message contained a numerical system, atomic numbers, and the DNA structure, among other key elements. The message will take around 25,000 years to reach its destination!
