Diocese definition, an ecclesiastical district under the jurisdiction of a bishop. See more.
planetary nebulae represented here by the ring nebula are examples of emission nebulae an emission nebula is a nebula formed of ionized gases that emit light of various colors the most common source of ionization is high energy photons emitted from a nearby hot star
Planetary nebulae are shells of gas thrown out by some stars near the end of their lives. Our Sun will probably produce a planetary nebula in about 5 thousand million years. They have nothing at all to do with planets; the terminology was invented because they often look a little like planets in small telescopes.he gas and dust in the nebula emits light because it is irradiated by nearby emerging stars. Located at a distance of about 1,600 light years, the Orion nebula is the brightest diffuse nebula in the sky, visible to the naked eye.