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.
[in-fruh-son-ik] /ˌɪn frəˈsɒn ɪk/ adjective 1. noting or pertaining to a sound wave with a frequency below the audio-frequency range. adj. 1927, from infra- + sonic. infrasonic in·fra·son·ic (ĭn’frə-sŏn’ĭk) adj. Generating or using waves or vibrations with frequencies below that of audible sound. infrasound (ĭn’frə-sound’) Sound whose wave frequency is too low (under 15-20 hertz) […]
[in-fruh-son-iks] /ˌɪn frəˈsɒn ɪks/ noun, (used with a singular verb) 1. the branch of science that deals with phenomena.
[in-fruh-sound] /ˈɪn frəˌsaʊnd/ noun 1. with frequencies below the audible range. /ˈɪnfrəˌsaʊnd/ noun 1. soundlike waves having a frequency below the audible range, that is, below about 16Hz infrasound (ĭn’frə-sound’) Sound whose wave frequency is too low (under 15-20 hertz) to be heard by humans. Some animals, such as elephants and whales, emit calls at […]
[in-fruh-spi-sif-ik] /ˌɪn frə spɪˈsɪf ɪk/ adjective 1. of or relating to a subdivision of a species, as a subspecies, variety, or cultivar. /ˌɪnfrəspəˈsɪfɪk/ adjective 1. (biology) occurring within or affecting all members of a species: infraspecific variation infraspecific (ĭn’frə-spĭ-sĭf’ĭk) Occurring within a species; intraspecific.