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
Emission (bright line) One means by which a continuous spectrum can be produced is by thermal emission from a black body. This is particularly relevant in astronomy and is discussed in the next section. Astronomical spectra can be combination of absorption and emission lines on a continuous background spectrum.