Liquid-helium cryogenic system for onboard radiation collectors

Possible techniques are examined for cooling radiation collectors to 4 K under conditions encountered on board space stations, satellites, and rockets. It is shown that the use of liquid-helium cryostats is the most practical technique at the present time. A general arrangement is given for a system of onboard cryostats adapted for operation under zero g conditions. Results are presented for laboratory and inflight tests of models of such cryostats.