Worthwhile targets
Let’s begin with the brightest: NGC 6946. Sometimes called the Fireworks Galaxy because of its abundance of supernovae, this near-face-on Sc spiral can be a challenge because of its orientation. Face-on means you are seeing the galaxy’s disk from “above,” looking through a thin swath of the galaxy’s stars. But a modest aperture can still reveal NGC 6946’s spiral arms and more subtle features like regions filled with ionized hydrogen (HII regions), which are indicative of massive, young stars nearby. This isn’t the galaxy nearest the galactic plane on our list, so it shows more detail than many others featured here.
The most highly reddened galaxy on this list is the previously mentioned Maffei 1, located only 0.55° from the galactic plane. Astronomers estimate this galaxy suffers from about 4.7 magnitudes of extinction. It is an observing challenge requiring a 12-inch scope and very dark skies. If it were located any farther from the outer rim of the Milky Way, Maffei 1 wouldn’t be visible at all, even in infrared wavelengths.
IC 10 is an irregular galaxy in Cassiopeia. A member of the Milky Way’s Local Group of galaxies, it is faint, but bears magnification well. A large telescope will display its patchy nature. IC 10 is the only starburst galaxy in our galactic neighborhood. Like typical irregular galaxies, IC 10 lacks a central hub of older stars, although it has an HII region in its core. Its magnitude of 10.4 makes it sound easier to observe than it is, but with large optics, you can bring out its mottled texture.
A somewhat less challenging galaxy in the compact Milky Way constellation Lacerta is NGC 7231. At magnitude 13, this highly inclined barred spiral is visible using a 6- to 8-inch telescope under dark skies. It is located about 0.3° southwest of a 5th-magnitude field star and about 2° southeast of the large open cluster NGC 7209.