false-color imageryA process of color coding in the reproduction of an image in which colors unrelated to those of the original subject are used to indicate the distribution of certain quantities, such as the object's temperature, intensity of emitted radiation, etc. False-color images may be taken of such objects as the Sun, or over a region of the Earth, Sun, sky, etc. The colors are usually computer-generated. False color can also be used to indicate velocity since different Doppler shifts from a single observational wavelength can be calculated and coded into different colors. In addition, images taken at different wavelengths, e.g. a radio and an optical wavelength, can each be allotted a color and can be superimposed to form a composite image. See also radio-source structure.
Collins Dictionary of Astronomy © Market House Books Ltd, 2006