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EM Spectrum (Light)

The Spectrum of Electromagnetic Radiation (Light)
Wavelength is defined as the distance between two peaks or lows in a wave
Electromagnetic radiation, another name for light, is a stream of photons (particles that don't have mass yet are traveling in a wave-like pattern while moving at the speed of light). Each photon contains a specific amount of energy. The important difference within the spectrum of electromagnetic radiation is the amount of energy found in the photons: photons of blue light have more energy than photons of green light and all other light with longer wavelengths.

View a movie (42.1 MB) that illustrates how light is created by atoms and molecules. 

About the electromagnetic spectrum

Since the movie is large, parts below describe how the different parts of
the electromagnetic spectrum are created by atoms and molecules.

Intro: Sources of light

Sources of light

Intended for middle school students, these movies are valuable for anyone interested in learning about light. Created by the Cassini-Huygens Satellite Mission to Saturn outreach team at NASA's Jet Propulsion Laboratory (JPL). Their interactive CD, Ways of Seeing, which includes this movie, is available at NASA 's Central Operation of Resources for Educators (CORE) and may be ordered on-line for $5.

Remote sensing

Remote sensing

Types of Electromagnetic (EM) waved by frequency. In order from highest to lowers frequency: Gamma Rays, X-Rays, Ultraviolet, visible light, Infrared, and then Radio, which includes Microwaves, FM, and AM.
Color Peak Wavelength[nm]
Blue 470
Cyan 525
Green 560
Yellow 585
Orange 600
Red 645
Deep Red 700

Illustrated resources on light and the electromagnetic spectrum may be found at the following sites: