The electromagnetic (EM) spectrum includes long wavelength and low frequency radio waves on one end, and short wave lehgth high frequency gamma rays on the other, with visible light as a narrow band in the middle.

 

 

The wavelength determines the type of electromagnetic radiation—whether it’s infrared, ultraviolet, or something else. Certain wavelengths can penetrate the Earth’s atmosphere; others cannot. The earth maintains its energy balance by either absorbing electromagnetic radiation or re-radiating the energy back into space.