GALAXIES

M51 (NGC5194), which is the larger galaxy on the left in the image, is the famous Whirlpool Galaxy in Canes Venatici. At a distance of approximately 23 million light years, it is one of the best known & most conspicuous spiral galaxies in the sky. M51 is interacting with its neighbor, NGC 5195, the smaller galaxy on the right. Charles Messier discovered M51 on October 13, 1773. The Whirlpool’s spiral pattern was not seen until 1845 by Lord Rosse. M51 is relatively easy to find, lying just southeast of the easternmost star at the end of the Big Dipper’s handle. The true extent of M51’s structure can only be gathered through long exposure photographs, and this image could definitely have benefited from another hour or two of data. M51 is comparable to the Andromeda galaxy (M31) and to our own Milky Way galaxy in size, mass, and luminosity. It has a radius of about 38,000 light years.

Visually, the two galaxies give the impression of being actually connected. But photographs reveal that this is not true, the dark dust lanes of the larger spiral actually curve in front of the smaller companion. With the advent of radio astronomy, it has been demonstrated that the two galaxies are definitely interacting. Hubble Space Telescope has explored the core of this galaxy which probably has a black hole. Capture & equipment details can be found here: M51 ( PSugg ) - AstroBin