Infrared radiation is below the visible spectrum (longer wavelengths), but above the radio portion of the spectrum. Infrared is considered to occur between wavelengths of 1 micron and 1 millimeter. Absorption by gases such as water vapor, carbon dioxide, and ozone prevent us from ground-based study of infrared (IF) except through a few 'windows'.

Our body and the entire world radiate at IF wavelengths and the problem facing infrared astronomers has been described as "comparable to that of an optical astronomer working in a lighted dome with a luminescent telescope." The objects of infrared study are cool, dim, and in general this means either stars that are dying (cooling off) or those stars that are just now forming and have not begun to radiate at visible frequencies: proto-stars.

Only a small fraction of the 6000-odd stars visible to the naked eye are prominent at IF wavelengths and an entire new set of constellations appear. Infrared radiation has been detected from the Sun, Moon, and several planets, in particular, Jupiter. Beyond the solar system, IF radiation has been associated with a great many red-faint stars, planetary nebulae, the galactic center, and other galaxies, in particular, the Seyfert galaxies.

The most interesting IF research involves attempts to discover the very young proto-stars in the vast dust complexes that are known to be the birth places of stellar bodies. The great Orion Nebula has received much attention, and astronomers believe stars are condensing and forming in these dark clouds at the present time. Infrared astronomy is quite young at the present time.

Copyright (c) 1997-99 Michael Erlewine