NGC 6946 is a bright galaxy sometimes called the Fireworks Galaxy due to its high rate of supernovae. It lies in a very rich star field right on the border of Cepheus and Cygnus.
This object is an intermediate spiral, meaning it structurally leans a little toward being a barred spiral. It was discovered by William Herschel in 1798. The galaxy lies approximately 25 million light-years away, placing it midway between our Local Group of galaxies and the Virgo Cluster.
NGC 6946 is a poster child for supernovae, which underscores its nickname. Bright supernovae in NGC 6946 have occurred in 1917, 1939, 1948, 1968, 1969, 1980, 2002, 2004, 2008, and 2017. This galaxy has shown at least 10 times the rate of supernova production as the Milky Way, and the magnitudes of these supernovae have ranged from 11 to 16.
Due to its extremely high production rate of stars, NGC 6946 has been classified as a starburst galaxy.
The galaxy shows some unusual structure, some of which is visible in very large amateur telescopes, and this includes several bubbles, large open clusters, and supernova remnants.
