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Links: Polyphonic Ringtones |
Infrared Astronomy is the detection and study of the infrared radiation (heat energy) emitted from objects in the Universe. Every object that has a temperature radiates in the infrared. So, Infrared Astronomy involves the study of just about everything in the Universe. In the field of astronomy, the infrared region lies within the range of sensitivity of infrared detectors, which is between wavelengths of about 1 and 300 microns (a micron is one millionth of a meter). The human eye detects only 1% of light at 0.69 microns, and 0.01% at 0.75 microns, and so effectively cannot see wavelengths longer than about 0.75 microns unless the light source is extremely bright. The Universe sends us a tremendous amount of information in the form of electromagnetic radiation (or light). Much of this information is in the infrared, which we cannot see with our eyes or with visible light telescopes. Only a small amount of this infrared information reaches the Earth's surface, yet by studying this small range of infrared wavelengths, astronomers have uncovered a wealth of new information. Only since the early 1980's have we been able to send infrared telescopes into orbit around the Earth, above the atmosphere which hides most of the Universe's light from us. The new discoveries made by these infrared satellite missions has been astounding. The first of these satellites - IRAS (Infrared Astronomical Satellite) - detected about 350,000 infrared sources, increasing the number of cataloged astronomical sources by about 70%. |