This is the Woody-Richards experiment, a balloon-borne Fourier transform far infrared spectrometer. It was one of the first projects designed to measure the microwave background discovered by Penzias and Wilson. To achieve maximum sensitivity the assembly was immersed in a cryostat cooled with superfluid helium at less than one degree absolute. The spectrometer was flown three times in the mid-1970s. The results from these experiments, announced in 1979, provided widely accepted data on the thermal characteristics of the cosmic background radiation, improved only by the announcement of data from instruments flown on the Cosmic Background Explorer (COBE) satellite. This experiment combined novel technologies that were later used on FIRAS/COBE. It was donated to NASM in 1997 by Professor Paul Richards of the Department of Physics at the University of California, Berkeley. It is now on display in the Explore the Universe gallery.
Donated by P. L. Richards, Department of Physics, University of California, Berkley