Galaxy NGC 5457

One of the most interesting and recent space objects made into Messier catalog, consisting of 110 celestial bodies, is a large spiral galaxy Pinwheel, also called Messier 101 or NGC 5457. This galaxy, located in the constellation Ursa Major, was opened by Frenchman Pierre Meshenom on March 27, 1781. Pinwheel galaxy is removed from us by 27 million light-years. Galaxy NGC 5457 has a well-defined spiral arms and a small compact bulge. Pinwheel Galaxy really has been very great. Its diameter is estimated at from 170,000 to 200,000 light years, nearly twice as much our Milky Way. Pinwheel Galaxy is known that in it registered three  supernova explosions, SN 1909A, SN 1951H and SN 1970G. Pinwheel Galaxy has a 5 companion galaxies, NGC 5204, NGC 5474, NGC 5477, NGC 5585.

source:www.infuture.ru