Abstract
A brief review is presented of the recent space cryogenic applications. There are many potential space missions requiring cryogenic cooling, some of which are in progress and others are still under consideration. Techniques for cryogenic cooling in space are discussed with emphasis on the temperature range and the refrigeration load. A He II cooled onboard infrared telescope which is indeed the highlight of the application of current space cryogenic technology is described by taking the IRTS as an example. Several new techniques required for the utilization of He II in space have been developed prior to the practical design studies of onboard IR telescopes. Some other projects, in addition to IR telescopes, requiring He II cooling are also briefly described. Finally, a prospect of future space cryogenics is discussed for further development of space cryogenics.
