An Etymological Dictionary of Astronomy and Astrophysics

That part of the → electromagnetic radiation lying beyond the red, between the radio and the visible regions of the → electromagnetic spectrum. The wavelengths range from about 0.8 → microns (μm) to about 1000 μm.

See also:

→ near-infrared; → mid-infrared; → far-infrared; → submillimeter radiation.

See also: → infrared; → radiation.