Galaxies are perhaps one of the most attractive deep-sky objects to observe and photograph. They represent massive collections of dust, gas and countless billions of stars and are best described as islands of space matter across the universe. They are characterized as being either spiral or elliptical in nature and usually have a bright central core. Equally stunning to observe (with large-aperture telescopes) and image are galaxy clusters which represent collections of gravitationally-bound groups of galaxies whose members number from tens to thousands and which are classified on the basis of their richness (ie. number of galaxy members), shape (spherical, flat or irregular) and content (spiral or elliptical). Charles Messier's list of deep-sky celestial gems includes approximately forty bright and large galaxies.

Note: The beautiful face-on galaxy NGC 6946 in Cepheus has the great distinction of having hosted eight supernova in less than one hundred years (SN 1917A, mag 14.6; SN 1939C, mag 13.0; SN 1948B, mag 14.9; SN 1968D, mag 13.5; SN 1969P, mag 13.9; SN 1980K, mag 11.4; SN 2002hh, mag 15.0; SN 2004et, mag 12.3) and, in fact, is the leading source of supernova discoveries to date. Lying at a relatively nearby distance of 10 million light-years away and spanning approximately 11'x10', it lies close to the galactic plane and which makes it somewhat obscure due to intergalactic dust which is believed to mitigate the overall brightness of this face-on galaxy. This galaxy was discovered by William Herschel in 1798. Due to its obvious asymmetry, NGC 6946 is also a member of Harold Arp's catalog of peculiar galaxies. Also known as the "Fireworks Galaxy", NGC 6946 is best observed during summer and early fall when it is directly overhead.