The Whirlpool Galaxy, Messier 51 or NGC 5194, is an interacting grand-design spiral galaxy with a Seyfert 2 active galactic nucleus in the constellation Canes Venatici. Recently it was estimated to be 23 ± 4 million light-years from the Milky Way. Messier 51 is one of the best known galaxies in the sky. The galaxy and its companion, NGC 5195, are easily observed by amateur astronomers. The Whirlpool Galaxy is also a popular target for professional astronomers, who study it to further understand galaxy structure and galaxy interactions.

Whirlpool Galaxy was discovered on October 13, 1773 by Charles Messier while hunting for objects that could confuse comet hunters, and was designated in his catalogue as M51. Its companion galaxy, NGC 5195, was discovered in 1781 by Pierre Méchain, although it was not known whether it was interacting or merely another galaxy passing at a distance. It was not until 1845 that William Parsons, employing a 72-inch (1.8 m) reflecting telescope at Birr Castle, Ireland, found the Whirlpool possessed a spiral structure, the first "nebula" to be known to have one. These "spiral nebulae" were not recognized as galaxies until Edwin Hubble was able to observe Cepheid variables in some of these spiral nebulae, which provided evidence that they were so far away that they must be entirely separate galaxies. [Source: Wikipedia]

CAPTURE Information:

The image was captured with the iOptron CEM120 mount , the venerable Meade 12"LX200 SCT, and my Atik 383L+ mono CCD at F7.16 (2182mm FL). Image subs were taken through Astronomik's filters Ha, Lum, R, G and B.

All subs were done at 1x1 bin, -10C, at 10 minutes each.

IMAGE information -- 2020

Lum (600s): 58 subs (9.67hr) on Jun 7th,8th, 9th,13th, 15th and 16th.

Ha (600s): 18 subs (3.00hr) on Jun 7th,8th and 9th.

Red (600s): 18 subs (3.00hr) on Jun 10th,13th and 14th.

Green(600s): 18 subs (3.00hr) on Jun 11th,13th and 14th.

Blue (600s): 18 subs (3.00hr) on Jun 10th,11th,13th and 14th.

Processing was done with PixInsight, following (for the most part) kayronjm's tutorial of Feb. 24th from several years back. Only L was used to develop the Luminance image. R, G and B were collected for the color mix.

Ha was combined with RED to accentuate the star burst activity in the spiral arms.

North is up (pretty sure, or not), and this is a very slight crop due to the various movement of different subs.

COMMENTS:

As with previous targets, I see I’ve imaged this one several times. Starting in 2011, then 2016 and 2017, then now. I think the latest is pretty good.

Using the Ha to accentuate the red starburst zones came out well.