This is an infrared (IR) view of Mt. Jian in Japan erupting in 1983. IR "light" is a form of electromagnetic radiation given off by hot materials like lava.
Click on image for full size
Daedalus Enterprises, Inc., Ann Arbor, MI

Electromagnetic Radiation

Electromagnetic radiation is the result of oscillating electric and magnetic fields. The wave of energy generated by such vibrations moves through space at the speed of light. And well it should... for visible light is indeed one form of electromagnetic (EM) radiation.

X-rays, radio waves, gamma rays, and infrared and ultraviolet "light" are the other main types of electromagnetic radiation. They are all traveling vibrations of electromagnetic waves, each with its own characteristic wavelength. Organized in order of wavelength, they make up the electromagnetic spectrum.

Sometimes it is useful to think about electromagnetic radiation as though it came in packets. These packets of EM radiation are called "photons".

There is a second main type of radiation, which is the result of subatomic particles moving at very high speeds. That type of radiation is called "particle radiation".

Last modified June 22, 2005 by Randy Russell.

You might also be interested in:

Traveling Nitrogen Classroom Activity Kit

Check out our online store - minerals, fossils, books, activities, jewelry, and household items!...more

Radio Waves

Radio waves are a type of electromagnetic radiation. A radio wave has a much longer wavelength than does visible light. We use radio waves extensively for communications. Radio waves have wavelengths as...more

Photon

Light is very strange. Sometimes it is best to think of light as a series of waves. At other times, it is useful to think of light as a swarm of particles. When we think of light as particles, we call...more

Radiation

Radiation comes in two basic types: electromagnetic radiation transmitted by photons, and particle radiation consisting of electrons, protons, alpha particles, and so forth. Electromagnetic radiation,...more

Particle Radiation

One main type of radiation, particle radiation, is the result of subatomic particles hurtling at tremendous speeds. Protons, cosmic rays, and alpha and beta particles are some of the most common types...more

Ozone in the Stratosphere

About 90% of the ozone in the Earth's atmosphere is found in the region called the stratosphere. This is the atmospheric layer between 16 and 48 kilometers (10 and 30 miles) above the Earth's surface....more

Electricity and Magnetism

Electricity and magnetism are two very important topics in the science of physics. We use electricity to power computers and to make motors go. Magnetism makes a compass point North and keeps notes stuck...more

Photodissociation

Photons are tiny bits of light and other kinds of electromagnetic radiation. Photons can sometimes break apart molecules. When this happens, it is called photodissociation. When a photon runs into a molecule,...more

Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA