
| Object Data | |
| Description | M51 is a classical example of an interacting galaxy pair. The primary galaxy (NGC5194) shows a significant disruption in the shape of one of its spiral arms, possibly caused by the gravitational attraction from its lesser companion (NGC5195). Although the companion galaxy is clearly entirely behind the outer arm of M51 along our line of site, its outer reaches have been stretched into a veritable "spray" of stars considerably larger than the galaxy itself. Spectroscopy shows the companion to have only a slightly larger red shift (2kps) than the primary galaxy. This is essentially no difference at all, considering that the earth orbits the sun with a velocity greater than 30kps. | 
| Constellation | Canes Venatici, the two hunting dogs of Bootes: Astarion and Chara. | 
| Right Ascension | 13h 30m 1s | 
| Declination | +47° 10' 43" | 
| Magnitude | 8.9 | 
| Angular size | 10.8 arcminutes | 
| Distance | 7.7 megaparsecs (25 million light years) | 
| Radial Velocity | 463 kilometers per second | 
| Image Data | |
| Photographer | Fred Lehman | 
| Main Scope | Meade 14" LX200GPS @ f/5.0 (1775mm) | 
| Guide Scope | Celestron 5" SCT @ f/7.5 (950mm) | 
| Guide Camera | SBIG STV | 
| Imaging Camera | Starlight Xpress MX7C | 
| Resolution | 780 x 580 @ 1.0 arcseconds per pixel | 
| Exposure | Ten exposures of two minutes each. Aligned, stacked, and processed with AstroArt. | 
| Date | March 17, 2004 | 
| Location | Mid Florida Star Gaze at Kye's Star Farm in Venus, Florida. |