Spectra+Types

There are three basic types of spectra we see in AGN. First there is the continuum spectrum. Continuum Spectra is describe as light that has not been obstructed at all. It is clean and has not passed through any type of dust or gas. Next there is the emission line spectrum. This type has large spikes in the graph that are known as emission lines. These emission lines are caused because the light passes through hot gas, which pushes them into a higher energy, making the graph spike there. Finally there is the absorption spectrum. Absorption spectrum has large drops in the graph known as absorption lines. These absorption lines are caused when light passes through cold gas, which absorbs energy from the light making its energy drop.

//Animation showing spectra types.//

http://en.wikipedia.org/wiki/Emission_lines