A telescope, similar in operation to an optical telescope, that is designed to detect infrared radiation. Because infrared radiation is emitted by warm objects, infrared telescopes need to be shielded from local heat sources, as by chilling them with liquid nitrogen or locating them in polar regions. Many are placed on high mountains or are mounted on balloons or satellites in order to place them above the lower atmosphere, where water vapor absorbs much of the incoming infrared radiation.
The American Heritage® Science Dictionary Copyright © 2011. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.