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**__// THE ELEC TRO MAG NETIC SPEC TRUM //__** The Electro Magnetic Spectrum is defined as... //...n.// The entire range of radiation extending in frequency from approximately 1023 hertz to 0 hertz or, in corresponding wavelengths, from 10-13 centimeter to infinity and including, in order of decreasing frequency, cosmic-ray photons, gamma rays, x-rays, ultraviolet radiation, visible light, infrared radiation, microwaves, and radio waves. ([])

Image from ([]) The electromagnetic spectrum is the range of all possible electromagnetic radiation frequencies.The "electromagnetic spectrum" (usually just //spectrum//) of an object is the characteristic distribution of electromagnetic radiation from that particular object.

Basically what the above statement is saying is that everything gives off a certain frequency (length) of rays. Depending on what type f ray it is, the higher or the lower the frequency the ray will be. Em spectrum waves may be and are usually described with the the characteristics suhc as frequency, wave length, and photon energy. As you can see from the chart above, as the wave moves from left to right, the wave length decreases, but the frequency and the energy of the particles increases as well.



 Here are the different types of radiation in the EM spectrum, in order from lowest energy to highest: [|Visible]: Yes, this is the part that our eyes see. Visible radiation is emitted by everything from fireflies to light bulbs to stars ... also by fast-moving particles hitting other particles. [|Ultraviolet]: We know that the Sun is a source of ultraviolet (or UV) radiation, because it is the UV rays that cause our skin to burn! Stars and other "hot" objects in space emit UV radiation. || (from the website [] )
 * [[image:http://imagine.gsfc.nasa.gov/Images/introduction/spectrum_radio.gif width="256" height="218" caption="Radio"]] || [|Radio]: Yes, this is the same kind of energy that radio stations emit into the air for your boom box to capture and turn into your favorite Mozart, Madonna, or Justin Timberlake tunes. But radio waves are also emitted by other things ... such as [|stars] and gases in space. You may not be able to dance to what these objects emit, but you can use it to learn what they are made of. ||
 * [[image:http://imagine.gsfc.nasa.gov/Images/introduction/spectrum_microwave.gif width="256" height="57" caption="Microwave"]] || [|Microwaves]: They will cook your popcorn in just a few minutes! Microwaves in space are used by [|astronomers] to learn about the structure of nearby galaxies, and our own Milky Way! ||
 * [[image:http://imagine.gsfc.nasa.gov/Images/introduction/spectrum_IR2UV.gif width="256" height="234" caption="Infrared to UV"]] || [|Infrared]: Our skin emits infrared light, which is why we can be seen in the dark by someone using night vision goggles. In space, IR light maps the [|dust] between stars.
 * [[image:http://imagine.gsfc.nasa.gov/Images/introduction/spectrum_xray.gif width="256" height="41" caption="X-ray"]] || [|X-rays]: Your doctor uses them to look at your bones and your dentist to look at your teeth. Hot gases in the [|Universe] also emit X-rays . ||
 * [[image:http://imagine.gsfc.nasa.gov/Images/introduction/spectrum_gamma.gif width="256" height="140" caption="Gamma-ray"]] || [|Gamma-rays]: Radioactive materials (some natural and others made by man in things like nuclear power plants) can emit gamma-rays. Big particle accelerators that scientists use to help them understand what [|matter] is made of can sometimes generate gamma-rays. But the biggest gamma-ray generator of all is the Universe! It makes gamma radiation in all kinds of ways. ||


 * __PARTS OF THE ELECTRO MAGNETIC SPECTRUM...__**

 Radio Waves

...Radio waves have the longest wavelengths in the electromagnetic spectrum. These waves can be longer than a football field or as short as a football. Radio waves do more than just bring music to your radio. They also carry signals for your television and cellular phones. ...The antennae on your television set receive the signal, in the form of electromagnetic waves, that is broadcasted from the television station. It is displayed on your television screen. ...Cable companies have antennae or dishes which receive waves broadcasted from your local TV stations. The signal is then sent through a cable to your house.

(Information found at [] )

Microwaves picture from *([]) Electromagnetic spectrum with visible light highlighted Apparatus and techniques may be described qualitatively as "microwave" when the wavelengths of signals are roughly the same as the dimensions of the equipment, so that lumped-element circuit theory is inaccurate. As a consequence, practical microwave technique tends to move away from the discrete resistors, capacitors, and inductors used with lower frequency radio waves. Instead, Infrared
 * Microwaves** are electromagnetic waves with wavelengths ranging from 1mm - 1m, or frequencies between 0.3 GHz and 300 GHz.


 * Visible Light

The** visible spectrum **is the portion of the [|electromagnetic spectrum] that is [|visible] to (can be detected by) the human [|eye]. [|Electromagnetic radiation] in this range of [|wavelengths] is called** visible light **or simply [|light]. A typical human eye will respond to wavelengths from about [|380 to 750 nm].[|[1]] In terms of frequency, this corresponds to a band in the vicinity of 790–400 [|terahertz]. A light-adapted eye generally has its maximum sensitivity at around 555 [|nm] (540 THz), in the [|green] region of the optical spectrum (see: [|luminosity function]). The spectrum does not, however, contain all the [|colors] that the human eyes and brain can distinguish. [|Unsaturated colors] such as [|pink], and [|purple] colors such as [|magenta] are absent, for example, because they can only be made by a mix of multiple wavelengths.** Wavelengths visible to the eye also pass through the "[|optical window]", the region of the electromagnetic spectrum which passes largely unattenuated through the [|Earth's atmosphere] (although blue light is [|scattered] more than red light, which is the reason the sky appears blue). The response of the human eye is defined by subjective testing (see [|CIE]), but the atmospheric windows are defined by physical measurement. The "visible window" is so called because it overlaps the human visible response spectrum; the near infrared (NIR) windows lie just out of human response window, and the Medium Wavelength IR (MWIR) and Long Wavelength or Far Infrared (LWIR or FIR) are far beyond the human response region. The eyes of many [|species] perceive wavelengths different from the spectrum visible to the human eye. For example, many [|insects], such as [|bees], can see light in the [|ultraviolet], which is useful for finding [|nectar] in [|flowers]. For this reason, plant species whose life cycles are linked to insect pollination may owe their reproductive success to their appearance in ultraviolet light, rather than how colorful they appear to our eyes. Birds too are able to see into the ultraviolet (300-400 nm) and the sex-dependent markings on some bird plumage is only visible in the ultraviolet range.[|[2]][|[3]] (information found on [] )

Ultraviolet

X-Rays X-Rays are the second highest energy wave on the electromagnetic spectrum. They have a frequency of x-rays are about 10 to the 17th power and a wave length of 10 to the -10th power. High amounts of exposure to this wave frequency without proper protection can cause genetic damage and cancer. The most common protection from x-ray radiation is lead. X-rays are very useful in our world. The most common use of x-rays are in hospital x-ray machines. This allows doctors to look inside of a patient without having to cut them open. X-rays were discovered on November 8th, 1895, by a scientist by the name of Wilhelm Conrad Röntgen.

**Gamma Rays** Gamma rays are electromagnetic radiation of high energy. They are produced by sub-atomic particle interactions, such as electron-positro annihilation radioactive decay or inverse Compton scattering in astrophysical processes. Gamma rays typically have frequencies above 1019(Really Big) Hz and therefore energies above 100 keV and wavelength less than 10 picometers.(Really Small) Paul Villard, a French chemist and physicist, discovered Gamma radiation in 1900, while studying uranium.After gamma-irradiation, and the breaking of DNA double-strands, a cell can repair the damaged genetic material to the limit of its capability. photo from  This depiction of electromagnetic spectrum shows several objects with size scales comparable to the wavelengths of the waves of different types of electromagnetic radiation. Note that the range of wavelengths vary by many orders of magnitude, while the waves shown in this "cartoon" do not. For example, visible light waves are typically 100 times shorter than infrared waves, not just slightly shorter as depicted pictorially. **Credit:** Image courtesy of NASA's " [|Living With a Star] " program and the Center for Science Education at Space Sciences Laboratory, University of California at Berkeley.

Electromagnetic radiation interacts with matter in different ways in different parts of the spectrum. The types of interaction can be so different that it seems to be justified to refer to different types of radiation. At the same time there is a continuum containing all these "different kinds" of electromagnetic radiation. Thus we refer to a spectrum, but divide it up based on the different interactions with matter.


 * __ Other Information: __**

http://www.absoluteastronomy.com/topics/Electromagnetic_spectrum
 * ~ Region of the spectrum ||~ Main interactions with matter ||
 * Radio || Collective oscillation of charge carriers in bulk material (plasma oscillation). An [|antenna] is an example. ||
 * Microwave through far infrared || Plasma oscillation, molecular rotation ||
 * Near infrared || Molecular vibration, plasma oscillation (in metals only) ||
 * Visible || Molecular electron excitation (including pigment molecules found in the human retina), plasma oscillations (in metals only) ||
 * Ultraviolet || Excitation of molecular and atomic valence electrons, including ejection of the electrons ([|photoelectric effect]) ||
 * X-rays || Excitation and ejection of core atomic electrons ||
 * Gamma rays || Energetic ejection of core electrons in heavy elements, excitation of atomic nuclei, including dissociation of nuclei ||
 * High energy gamma rays || Creation of particle-antiparticle pairs. At very high energies a single photon can create a shower of high energy particles and antiparticles upon interaction with matter. ||

**Wavelength**  means pretty much what it says - the length of one wave.

More precisely, it means the **distance from the peak of one wave to the peak on the next wave**. Strictly speaking, "the distance from any point on a wave to the same point on the next cycle of the wave". The peaks are just handy places to measure from. It may be measured in:

**Frequency**  is a word used in Maths to mean "how often something happens".
 * <span style="font-family: Arial, Helvetica, sans-serif;">kilometres || <span style="font-family: Arial, Helvetica, sans-serif;">km || <span style="font-family: Arial, Helvetica, sans-serif;">1,000 metres ||
 * <span style="font-family: Arial, Helvetica, sans-serif;">metres || <span style="font-family: Arial, Helvetica, sans-serif;">m || <span style="font-family: Arial, Helvetica, sans-serif;">//Awww, come on, you know how big a metre is!// ||
 * <span style="font-family: Arial, Helvetica, sans-serif;">centimetres || <span style="font-family: Arial, Helvetica, sans-serif;">cm || <span style="font-family: Arial, Helvetica, sans-serif;">A hundredth of a metre. But you know this already. ||
 * <span style="font-family: Arial, Helvetica, sans-serif;">millimetres || <span style="font-family: Arial, Helvetica, sans-serif;">mm || <span style="font-family: Arial, Helvetica, sans-serif;">1/1000th of a metre. Those tiny lines on your ruler! ||
 * <span style="font-family: Arial, Helvetica, sans-serif;">nanometres || <span style="font-family: Arial, Helvetica, sans-serif;">nm || <span style="font-family: Arial, Helvetica, sans-serif;">1/1000,000,000th of a metre. Or, if you prefer, a millionth of a millimetre. Small! ||

With waves, it's "**how many waves per second**" It may be measured in:

Your favourite FM radio station probably broadcasts around 100 MHz ||
 * <span style="font-family: Arial, Helvetica, sans-serif;">Hertz || <span style="font-family: Arial, Helvetica, sans-serif;">Hz || <span style="font-family: Arial, Helvetica, sans-serif;">1 Hz means 1 wave per second ||
 * <span style="font-family: Arial, Helvetica, sans-serif;">kilohertz || <span style="font-family: Arial, Helvetica, sans-serif;">kHz || <span style="font-family: Arial, Helvetica, sans-serif;">1 kHz is 1,000 waves per second ||
 * <span style="font-family: Arial, Helvetica, sans-serif;">megahertz || <span style="font-family: Arial, Helvetica, sans-serif;">MHz || <span style="font-family: Arial, Helvetica, sans-serif;">1 MHz is 1 million waves per second.
 * <span style="font-family: Arial, Helvetica, sans-serif;">gigahertz || <span style="font-family: Arial, Helvetica, sans-serif;">GHz || <span style="font-family: Arial, Helvetica, sans-serif;">1 GHz is 1,000 million waves per second. Microwaves are around a few GHz. ||

information from: (http://home.clara.net/darvill/emag/index.html)

The electromagnetic spectrum covers a wide range of wavelengths and photon energies. Light used to "see" an object must have a wavelength about the same size as or smaller than the object. The ALS generates light in the far ultraviolet and soft x-ray regions, which span the wavelengths suited to studying molecules and atoms. =The Electromagnetic Spectrum= all electromagnetic radiation -- from radio waves to x-rays -- travel at the speed of light. In empty space this speed is approximately 300,000 kilometers per second! We can even predict the wavelength of an electromagnetic wave if we know the time it takes for the charge to oscillate once, returning to its original location. This time is called the "period", T, of the wave. By multiplying the period with the speed of light (c), we can determine the wavelength of any wave. The frequency, "f," is the number of completed periods in one second. If the period is 1/2 second, the frequency will be two wavelengths per second (1/2 second for one wavelength, so two wavelengths in one second). In general, (Angstroms)** || **Wavelength (centimeters)** || **Frequency (Hz)** || **Energy (eV)** ||
 * ~ Spectrum of Electromagnetic Radiation ||
 * **Region** || **Wavelength
 * Radio || > 109 || > 10 || < 3 x 109 || < 10-5 ||
 * Microwave || 109 - 106 || 10 - 0.01 || 3 x 109 - 3 x 1012 || 10-5 - 0.01 ||
 * Infrared || 106 - 7000 || 0.01 - 7 x 10-5 || 3 x 1012 - 4.3 x 1014 || 0.01 - 2 ||
 * Visible || 7000 - 4000 || 7 x 10-5 - 4 x 10-5 || 4.3 x 1014 - 7.5 x 1014 || 2 - 3 ||
 * Ultraviolet || 4000 - 10 || 4 x 10-5 - 10-7 || 7.5 x 1014 - 3 x 1017 || 3 - 103 ||
 * X-Rays || 10 - 0.1 || 10-7 - 10-9 || 3 x 1017 - 3 x 1019 || 103 - 105 ||
 * Gamma Rays || < 0.1 || < 10-9 || > 3 x 1019 || > 105 ||

The Electromagnetic Spectrum
The electromagnetic spectrum is a continuum of all electromagnetic waves arranged according to frequency and wavelength. The sun, earth, and other bodies radiate electromagnetic energy of varying wavelengths. Electromagnetic energy passes through space at the speed of light in the form of sinusoidal waves. The wavelength is the distance from wavecrest to wavecrest (see figure below). Light is a particular type of electromagnetic radiation that can be seen and sensed by the human eye, but this energy exists at a wide range of wavelengths. The micron is the basic unit for measuring the wavelength of electomagnetic waves. The spectrum of waves is divided into sections based on wavelength. The shortest waves are gamma rays, which have wavelengths of 10e-6 microns or less. The longest waves are radio waves, which have wavelengths of many kilometers. The range of visible consists of the narrow portion of the spectrum, from 0.4 microns (blue) to 0.7 microns (red). =Ultraviolet Waves= Scientists have divided the ultraviolet part of the spectrum into three regions: the near ultraviolet, the far ultraviolet, and the extreme ultraviolet. The three regions are distinguished by how energetic the ultraviolet radiation is, and by the "wavelength" of the ultraviolet light, which is related to energy. The near ultraviolet, abbreviated NUV, is the light closest to optical or visible light. The extreme ultraviolet, abbreviated EUV, is the ultraviolet light closest to X-rays, and is the most energetic of the three types. The far ultraviolet, abbreviated FUV, lies between the near and extreme ultraviolet regions. It is the least explored of the three regions. Though some ultraviolet waves from the Sun penetrate Earth's atmosphere, most of them are blocked from entering by various gases like Ozone. Some days, more ultraviolet waves get through our atmosphere. Scientists have developed a UV index to help people protect themselves from these harmful ultraviolet waves.
 * Ultraviolet (UV) light has shorter wavelengths than visible light. Though these waves are invisible to the human eye, some insects, like bumblebees, can see them! (Image of the bumblebee is courtesty of Mark Cassino.) || [[image:http://science.hq.nasa.gov/kids/imagers/ems/bumblebee2.jpg width="216" height="181" caption="An image of a bumblebee."]] ||
 * [[image:http://science.hq.nasa.gov/kids/imagers/ems/latest_eit_171.jpg width="216" height="216" align="center" caption="The Extreme Ultraviolet Sun."]] || Our Sun emits light at all the different wavelengths in electromagnetic spectrum, but it is ultraviolet waves that are responsible for causing our sunburns. To the left is an image of the Sun taken at an Extreme Ultraviolet wavelength - 171 Angstroms to be exact. (An Angstrom is a unit length equal to 10-10 meters.) This image was taken by a satellite named SOHO and it shows what the Sun looked like on April 24, 2000. ||

How do we "see" using Ultraviolet light?
It is good for humans that we are protected from getting too much ultraviolet radiation, but it is bad for scientists! Astronomers have to put ultraviolet telescopes on satellites to measure the ultraviolet light from stars and galaxies - and even closer things like the Sun!
 * There are many different satellites that help us study ultraviolet astronomy. Many of them only detect a small portion of UV light. For example, the Hubble Space Telescope observes stars and galaxies mostly in near ultraviolet light. NASA's Extreme Ultraviolet Explorer satellite is currently exploring the extreme ultraviolet universe. The International Ultraviolet Explorer (IUE) satellite has observed in the far and near ultraviolet regions for over 17 years. || [[image:http://science.hq.nasa.gov/kids/imagers/ems/iue.gif width="232" height="282" caption="The International Ultraviolet Explorer"]] ||

What does Ultraviolet light show us?
We can study stars and galaxies by studying the UV light they give off - but did you know we can even study the Earth? Below is an unusual image - it is a picture of Earth taken from a lunar observatory! This false-color picture shows how the Earth glows in ultraviolet (UV) light. Many scientists are interested in studying the invisible universe of ultraviolet light, since the hottest and the most active objects in the cosmos give off large amounts of ultraviolet energy. The image below shows three different galaxies taken in visible light (bottom three images) and ultraviolet light (top row) taken by NASA's Ultraviolet Imaging Telescope (UIT) on the Astro-2 mission. The difference in how the galaxies appear is due to which type of stars shine brightest in the optical and ultraviolet wavelengths. Pictures of galaxies like the ones below show mainly clouds of gas containing newly formed stars many times more massive than the sun, which glow strongly in ultraviolet light. In contrast, visible light pictures of galaxies show mostly the yellow and red light of older stars. By comparing these types of data, astronomers can learn about the structure and evolution of galaxies. [[image:http://science.hq.nasa.gov/kids/imagers/ems/IR.gif width="275" height="125" align="center" caption="Diagram of the infrared part of the spectrum showing the far, mid, and near ranges."]] Infrared light is even used to heat food sometimes - special lamps that emit thermal infrared waves are often used in fast food restaurants!|| Shorter, near infrared waves are not hot at all - in fact you cannot even feel them. These shorter wavelengths are the ones used by your TV's remote control. || ||
 * The Far UV Camera/Spectrograph deployed and left on the Moon by the crew of Apollo 16 took this picture. The part of the Earth facing the Sun reflects much UV light. Even more interesting is the side facing away from the Sun. Here, bands of UV emission are also apparent. These bands are the result of aurora caused by charged particles given off by the Sun. They spiral towards the Earth along Earth's magnetic field lines. || [[image:http://science.hq.nasa.gov/kids/imagers/ems/uvEarth_ap16.jpg width="288" height="239" caption="The UV Earth"]] [[image:http://science.hq.nasa.gov/kids/imagers/ems/dlink.gif caption="D" link="http://science.hq.nasa.gov/kids/imagers/ems/uv_earth.html"]] ||
 * =The Infrared=
 * Infrared light** lies between the visible and microwave portions of the electromagnetic spectrum. Infrared light has a range of wavelengths, just like visible light has wavelengths that range from red light to violet. "Near infrared" light is closest in wavelength to visible light and "far infrared" is closer to the microwave region of the electromagnetic spectrum. The longer, far infrared wavelengths are about the size of a pin head and the shorter, near infrared ones are the size of cells, or are microscopic. ||
 * [[image:http://science.hq.nasa.gov/kids/imagers/ems/campfire.jpg caption="Campfire."]] || Far infrared waves are thermal. In other words, we experience this type of infrared radiation every day in the form of heat! The heat that we feel from sunlight, a fire, a radiator or a warm sidewalk is infrared. The temperature-sensitive nerve endings in our skin can detect the difference between inside body temperature and outside skin temperature ||

How can we "see" using the Infrared?
Since the primary source of infrared radiation is heat or thermal radiation, any object which has a temperature radiates in the infrared. Even objects that we think of as being very cold, such as an ice cube, emit infrared. When an object is not quite hot enough to radiate visible light, it will emit most of its energy in the infrared. For example, hot charcoal may not give off light but it does emit infrared radiation which we feel as heat. The warmer the object, the more infrared radiation it emits. The image at the left (courtesy of SE-IR Corporation, Goleta, CA) shows a cat in the infrared. The orange areas are the warmest and the white-blue areas are the coldest. This image gives us a different view of a familiar animal as well as information that we could not get from a visible light picture. || Humans may not be able to see infrared light, but did you know that snakes in the pit viper family, like rattlesnakes, have sensory "pits", which are used to image infrared light? This allows the snake to detect warm blooded animals, even in dark burrows! Snakes with 2 sensory pits are even thought to have some depth perception in the infrared! (Thanks to NASA's Infrared Processing and Analysis Center for help with the text in this section.) Many things besides people and animals emit infrared light - the Earth, the Sun, and far away things like stars and galaxies do also! For a view from Earth orbit, whether we are looking out into space or down at Earth, we can use instruments on board satellites. Landsat 7 || Other satellites, like the Infrared Astronomy Satellite (IRAS) look up into space and measure the infrared light coming from things like large clouds of dust and gas, stars, and galaxies!
 * Humans, at normal body temperature, radiate most strongly in the infrared at a wavelength of about 10 microns. (A micron is the term commonly used in astronomy for a micrometer or one millionth of a meter.) This image ( which is courtesy of the Infrared Processing and Analysis Center at CalTech), shows a man holding up a lighted match! Which parts of this image do you think have the warmest temperature? How does the temperature of this man's glasses compare to the temperature of his hand? || [[image:http://science.hq.nasa.gov/kids/imagers/ems/ir_man.gif width="120" height="120" caption="Infrared man"]] [[image:http://science.hq.nasa.gov/kids/imagers/ems/dlink.gif caption="D" link="http://science.hq.nasa.gov/kids/imagers/ems/ir_man.html"]] ||
 * [[image:http://science.hq.nasa.gov/kids/imagers/ems/ircat.gif width="256" height="256" caption="Infrared image of a cat."]][[image:http://science.hq.nasa.gov/kids/imagers/ems/dlink.gif caption="D" link="http://science.hq.nasa.gov/kids/imagers/ems/ircat.html"]] || To make infrared pictures like the one above, we can use special cameras and film that detect differences in temperature, and then assign different brightnesses or false colors to them. This provides a picture that our eyes can interpret.
 * Satellites like GOES 6 and Landsat 7 look at the Earth. Special sensors, like those aboard the Landsat 7 satellite, record data about the amount of infrared light reflected or emitted from the Earth's surface. || [[image:http://science.hq.nasa.gov/kids/imagers/ems/landsat7.gif width="360" height="244" caption="Artist's conception of Landsat 7 orbiting the Earth."]]

What does the Infrared show us?
Why use the infrared to image the Earth? While it is easier to distinguish clouds from land in the visible range, there is more detail in the clouds in the infrared. This is great for studying cloud structure. For instance, note that darker clouds are warmer, while lighter clouds are cooler. Southeast of the Galapagos, just west of the coast of South America, there is a place where you can distinctly see multiple layers of clouds, with the warmer clouds at lower altitudes, closer to the ocean that's warming them. || Space Science and Engineering Center, University of Wisconsin-Madison, Richard Kohrs, designer || We know, from looking at an infrared image of a cat, that many things emit infrared light. But many things also reflect infrared light, particularly near infrared light. Near infrared radiation is not related to the temperature of the object being photographed - unless the object is very, very hot. Infrared film 'sees' the object because the Sun (or some other light source) shines infrared light on it and it is reflected or absorbed by the object. You could say that this reflecting or absorbing of infrared helps to determine the object's 'color' - its color being a combination of red, green, blue, and infrared! This image of a building with a tree and grass shows how Chlorophyll in plants reflect near infrared waves along with visible light waves. Even though we can't see the infrared waves, they are always there. The visible light waves drawn on this picture are green, and the infrared ones are pale red. || || Instruments on board satellites can also take pictures of things in space. The image below of the center region of our galaxy was taken by IRAS. The hazy, horizontal S-shaped feature that crosses the image is faint heat emitted by dust in the plane of the Solar System. Infrared Processing and Analysis Center, Caltech/JPL || [] [] **<span style="font-size: 10pt; line-height: 115%; font-family: 'Times New Roman','serif'; mso-fareast-font-family: 'Times New Roman'; mso-ansi-language: EN-US; mso-font-kerning: 18.0pt;">[] ** [] [] []
 * This is an infrared image of the Earth taken by the GOES 6 satellite in 1986. A scientist used temperatures to determine which parts of the image were from clouds and which were land and sea. Based on these temperature differences, he colored each separately using 256 colors, giving the image a realistic appearance.
 * This image was taken with special film that can detect invisible infrared waves. This is a false-color image, just like the one of the cat. False-color infrared images of the Earth frequently use a color scheme like the one shown here, where infrared light is mapped to the visible color of red. This means that everything in this image that appears red is giving off or reflecting infrared light. This makes vegetation like grasa and trees appear to be red. The visible light waves drawn on this picture are green, and the infrared ones are darker red. || [[image:http://science.hq.nasa.gov/kids/imagers/ems/treeIR.jpg width="250" height="200" caption="Same building and tree on infrared film."]] ||
 * [[image:http://science.hq.nasa.gov/kids/imagers/ems/IR.jpg width="250" height="250" caption="Landsat 5 image of Phoenix, Arizona"]] [[image:http://science.hq.nasa.gov/kids/imagers/ems/dlink.gif caption="D" link="http://science.hq.nasa.gov/kids/imagers/ems/ir_arizona.html"]] || This is an image of Phoenix, Arizona showing the near infrared data collected by the Landsat 5 satellite. The light areas are areas with high reflectance of near infrared waves. The dark areas show little reflectance. What do you think the black grid lines in the lower right of this image represent? ||
 * [[image:http://science.hq.nasa.gov/kids/imagers/ems/cmposit.jpg width="250" height="250" caption="False-color image of Pheonix, Arizona"]] [[image:http://science.hq.nasa.gov/kids/imagers/ems/dlink.gif caption="D" link="http://science.hq.nasa.gov/kids/imagers/ems/cmposit.html"]] || This image shows the infrared data (appearing as red) composited with visible light data at the blue and green wavelengths. If near infrared is reflected off of healthy vegetation, what do you think the red square shaped areas are in the lower left of the image? ||