Whirlpool Galaxy (M 51)

clic for 36% size 1367 x 819 (238 kB)

clic here for 60% size 2278 x 1531 (533 kB)

 

About this Image

M51, the famous Whirlpool Galaxy is the dominating member of a small group of galaxies in Canes Venatici. As it is about 37 million light years distant and so conspicuous, it is actually a big and luminous galaxy.
To the left side we see the gravitational effects of a close encounter with NGC 5195, the small, yellowish galaxy at the outermost tip of one of the Whirlpool's arms, in reality behind the main disk.
A lot of background galaxies can be seen in the widefield image.
North is to the left.

Find a famous Hubble mosaic on M 51 here.

Below you see a crop on the center of the above image in 40/80% size.

clic for 80% size 1749 x 1200 (448 kB)

 


Technical Details

Optics

16" cassegrain in secondary focus at f/10

Mount MK-100 GEM
Camera SBIG STL-11000M at -25C, internal filter wheel
Filters Baader L; Astronomik RGB
Date RGB: April 2005, L: January 2009
Location Wildon/Austria
Sky Conditions mag 5 sky, raw FWHM 1.3-1.6" (L), 1.6-2.2" RGB, temperature -5 to 5 C
Exposure L:R:G:B = 300:60:60:60 minutes (20-minute sub-exposures),
Processing Image aquisition in Maxim, image calibration, aligning, DDP in CCDStack; color balance, curves, unsharp mask in Photoshop;
north is to the left;