NGC7217 is a flocculent spiral galaxy high in the nothern sky in late summer, into the winter, about 50
million light years from us. While there is an obvious sprial structure, there are no spiral "arms" like one often sees in a sprial galaxy.
It has a series of three visible ringlike zones: a nuclear ring 21 arcseconds/5,000 light years in diameter (the very brightest part in the center of the image), a weak inner ring 63
arcseconds/15,000 lighte years in diameter (the yellow part outside of the innter ring), and an outer ring about 3 arcminutes/43,000 light years in diameter (about a third of the diameter
of our Milky Way). The origin of the ring features is uncertain. It is surmised that this unusual structure may be the result of one or more mergers with other galaxies.
This photo shows the significant halo around the disc of the galaxy.
The entire field of the uncropped version of the photo is about the same width as a full moon.
Copyright 2021 Mark de Regt