Calling this object a “nebula” is a bit of a misnomer, but galaxy IC 2574 does feature impressively large star-forming regions.
Coddington’s Nebula, the galaxy IC 2574, imaged in high resolution shows a multitude of HII regions within the system. Credit: Mark Hanson
Coddington’s Nebula is an obscure, fuzzy object discovered by the American astronomer Edwin Coddington (1870–1950) in 1898. The popular name for this object is a misnomer; it’s actually a galaxy, and was identified as such by the 1930s, in the era when Edwin Hubble was working through the initial classification of galaxies. It is also catalogued as IC 2574.
This dwarf barred spiral galaxy lies in Ursa Major, about 13 million light-years away. It is notable because it contains ample evidence of recent star formation, with multiple star-forming regions. The diameters of some of the HII regions in the galaxy are 85 to 500 light-years across — impressive!
It’s an outlying member of the M81 Group of galaxies, which also includes M81, M82, NGC 2403, and two dozen others, mostly dwarf ellipticals.
About 90 percent of the mass of IC 2574 exists in the form of dark matter.
This galaxy glows at magnitude 10.7 and spans 12′ by 6′, making it visible in backyard scopes, although its surface brightness is low.
