Michael P. Caligiuri from Carlsbad, California
CTB 1 (Abell 85) is a faint supernova remnant in Cassiopeia roughly 9,800 light-years distant. Originally classified by George Abell as a planetary nebula, it’s over half a degree wide — larger in apparent size than a Full Moon. This Hα/OIII/RGB image was taken with a 4.2-inch refractor at f/5 and 8.25 hours of exposure.