A far-infrared radiometer, cooled to 1.6 K by superfluid helium, has been flown in a Terrier—Sandhawk rocket. The instrument was designed to measure night-sky radiation in three wavelength passbands between 6 mm and 0.1 mm at altitudes between 120 km and 350 km. A failure in the rocket nose cone separation system prevented the measurement of this radiation, but the performance of the instrument during flight was generally satisfactory. Design features and operational characteristics of the cryogenic, optical, detection, and electronic systems are presented.
A. G. Blair, F. Edeskuty, R. D. Hiebert, D. M. Jones, J. P. Shipley, and K. D. Williamson, Jr., "Superfluid-Helium-Cooled Rocket-Borne Far-Infrared Radiometer," Appl. Opt. 10, 1043-1050 (1971)