Infrared radiation is a segment of the electromagnetic spectrum typified by its long wave lengths. These waves are substantially longer than the shorter wave lengths of other electromagnetic radiation, such as X-rays and gamma rays, and contain less energy than short wave lengths, making them less dangerous to organic life.
Most infrared radiation is not detectable by human eyes, although it is possible to experience its presence through the sensation of heat. Infrared radiation is used in some night vision devices to detect thermal signatures and provide visuals. It is also used in astronomy by some telescopes to penetrate the dustier portions of space and view previously obscured cosmological bodies or phenomenon.