M51 - Whirpool Galaxy

The Whirlpool Galaxy (also known as Messier 51a, M51a, or NGC 5194) is an interacting[5] grand-design[6] spiral galaxy located at a distance of approximately 23 million light-years in the constellation Canes Venatici. It is one of the most famous galaxies in the sky.

What was later known as the Whirlpool Galaxy was discovered[9] in 1774 by Charles Messier, and is designated as M51. Its companion galaxy, NGC 5195, was discovered in 1781 by Pierre Méchain. It was however not until 1845 that the Whirlpool became the first to be recognized as a spiral. Sometimes M51 is used to refer to the pair of galaxies, in which case the individual galaxies may be referred to as M51A (NGC 5194) and M51B (NGC 5195).

Telescope: Skywatcher ED80 & William Optics FF/FR 0.8 II
Mount: HEQ5 Pro
Camera: QHY8
Filter: IDAS LPS
Guidescope: Skywatcher 70/500mm
Guide with LVI SmartGuider
Exp. Time: 3 hours (9*20 min subframes)
Calibration Frames: 50 flat, 50 bias, 10 darks
Capture: Nebulosity 2.2.5
Stack: Deep Sky Stacker
Processing: Photoshop CS3
Date: 2 April 2010
Location: Ancient Epidauros, GR

M51 - Whirpool Galaxy Wiki