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
This causes the nebula to glow. Emission nebulae tend to be red in color because of the abundance of hydrogen. Additional colors, such as blue and green, can be produced by the atoms of other elements, but hydrogen is almost always the most abundant. A fine example of an emission nebula is the Orion Nebula (M42).Reflection Nebula-A reflection nebula differs from an emission nebula in does not emit radiation of its own. It is a cloud of dust and gas that reflects the light energy from a nearby star or group of stars.his causes the nebula to glow. Emission nebulae tend to be red in color because of the abundance of hydrogen. Additional colors, such as blue and green, can be produced by the atoms of other elements, but hydrogen is almost always the most abundant. A fine example of an emission nebula is the Orion Nebula (M42).