Far-Infrared Surveys of the Sky

See allHide authors and affiliations

Science  14 Jul 1967:
Vol. 157, Issue 3785, pp. 187-189
DOI: 10.1126/science.157.3785.187


A series of far-infrared surveys of the sky is searching for thermal radiation from interstellar grains and for other localized sources of far-infrared radiation. A balloon-borne germanium bolometer, cooled by liquid helium, is used in association with a telescope and spectral filters. During two initial flights the response to a black-body source was mainly between 300 and 360 microns. Approximately half the celestial sphere was surveyed, including most of the northern Milky Way. The angular resolution was 2 degrees. Moon was the only source of thermal radiation detected. The upper limit on the differential flux, relative to background, from other sources was 2 x 10-23 watt per square centimeter per hertz, corresponding to an antenna temperature of 0.6°K in the Rayleigh-Jeans approximation, or 10°K for a black body.