Abell 39 is a planetary nebula in Hercules. It is 6 light years across with a bright rim ~0.3 light years wide and is 7,000 light years distant. It has low surface brightness and strongly emits OIII and weakly H-a. This is 2 hours of OIII taken on June 1st, 2014. It is almost perfectly circular, but its central blue mag 15.4 proginator star is not perfectly centered within the sphere for reasons unknown. It is estimated that is has been expanding for about 22,000 years.