Surface tension confined liquid cryogen cooler

A cryogenic cooler for use in craft such as launch, orbital and space vehicles subject to changes in orientation and conditions of vibration and weightlessness comprising:

• an insulated tank;
• a porous open celled sponge-like material disposed substantially throughout the contained volume of said insulated tank;
• a cryogenic fluid disposed within said sponge-like material;
• a cooling finger immersed in said cryogenic fluid, said finger extending from inside said insulated tank externally to an outside source such as an instrument detector for the purpose of transmitting heat from said outside source into said cryogenic fluid;
• means for filling said insulated tank with cryogenic fluid;
• and
• means for venting vaporized cryogenic fluid from said insulated tank;
• wherein said sponge-like material is of such pore size that the surface tension of said cryogenic fluid is effective to maintain said liquid cryogenic fluid suspended within said sponge-like material during conditions of vibration, changes in said cooler orientation and zero gravity environments, and
• wherein heat entering said cooling dewar through said cooling finger is conducted at a precise temperature through said cooling finger and therefrom into said cryogenic fluid contained within said tank, said heat being dissipated by vaporization and expulsion of cryogen through said vent means.