Space science Applications of Infra-Red Radiation

Infra-red radiation is a part of the electromagnetic spectrum, and is one of the ways in which thermal energy (or heat) are transferred from hot to cold objects. Any object will emit some IR radiation, depending how hot it is and what type of material it is made from. This fact is sometimes expolited in seeing things which otherwise might be difficult to see.

For example the image to the right shows how a person walking in front of a truck can be seen using far IR light, which is invisible to our eyes. The hotter the object, the brighter the image.

Thermal infra-red imaging is used primarily by NASA for earth bound satellite observation and by meteorological satellites, which can see through various weather conditions, and detect differences in temperature between clouds, sea and land.

Yellowstone fireThis image shows two photos side by side. The left image is a normal photo of the Yellowstone N.P. fire. On the right is a thermal satellite image, which can see through the smoke.


For a more detailed description of how thermal IR imaging is done, click here:NASA description

More information generally can be found at

NASA's Observatorium Education Resources homepage.


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