Rocket measurement of the cosmic background submillimeter spectrum

Measurements of the spectrum of the night sky have been made in the wave number region 5 to 35 cm/sup -1/ with use of a liquid helium cooled rocket-borne interferometer. The observed spectrum deviates from a 2.7 K Planck spectrum, there being a deficit of energy between 5 and 11 cm/sup -1/ and an excess at higher wave numbers.