Spectra

Spectra are very important to astronomy because they can show the component wavelengths and specific elements present.

Continuous Spectrum

Rectangular image of a continuous color spectrum from black to purple to blue to green to yellow to orange to red to black.
Public Domain | Image courtesy of Wikimedia Author: Jhausauer.

A continuous spectrum shows all wavelengths and is produced by hot, dense solid objects at high temperatures.

Emission Line Spectrum

Rectangular image of emission line spectrum show black with a small purple line, small blue line, small green line, and small red line. They are all seperate, not continuous.
Public Domain | Image courtesy of Wikimedia Author: Jhausauer.

An Emission Line spectrum produces a spectrum with bright lines . It occurs from heating an object, causing the electrons in the object’s atoms/molecules to show at a specific wavelength.

Absorption Line Spectrum

Rectangular image of the absorption line spectrum from black to purple to blue to green to yellow to orange to red to black. Throughout the spectrum there are small black line interupting the cotimious flow of color.
Public Domain | Image courtesy of Wikimedia Author: Jhausauer.

An Absorption Line spectrum produces a spectrum with dark lines . It occurs when one object absorbs specific photons given off by a second object. For example, a light behind a cloud of gas absorbs photons at the cloud’s energy level while the rest of the photons pass through the cloud.