NOVELTY - Microporous graphite foam is produced by forming a precursor matrix comprising graphite fibers and a graphite-forming precursor; first heating the matrix to a temperature at which the graphite-forming precursor is carbonized, forming a carbonized matrix; and second heating the carbonized matrix to a temperature at which the carbonized graphite-forming precursor is graphitized, forming the microporous graphite foam.    USE - The inventive process is used for producing microporous graphite foam (claimed) used in a cooling interface in the cryogenic cooling system (claimed). The cryogenic cooling system is used, e.g., in cooling electromagnetic energy detectors. The graphite foam is used in a heat sink, a heating element, an electrical conductor, a lightweight form-filling body for composite structures, cryostatic devices for cooling detectors, e.g. infrared, electron, X-ray or other radiation, a fuel cell, and/or a membrane for separation of conductive fluids.    ADVANTAGE - The inventive process produces the microporous graphite foam having pore sizes less than 10 microns, low bulk density and good physical strength for subsequent handling and machining into items having a shape other than a relatively simple molded shape. The produced graphite foam also has the desirable characteristics of graphite, including lightweight, high thermal conductivity, electrical conductivity and solderability.    DETAILED DESCRIPTION - Production of microporous graphite foam includes providing graphite fibers; mixing the graphite fibers with a graphite-forming precursor; compressing the mixture; forming a precursor matrix comprising the graphite fiber and the graphite-forming precursor; first heating the matrix to a temperature at which the graphite-forming precursor is carbonized, forming a carbonized matrix; and second heating the carbonized matrix to a temperature at which the carbonized graphite-forming precursor is graphitized, forming the microporous graphite foam. An INDEPENDENT CLAIM is also included for a cryogenic cooling system comprising the microporous graphite foam made by the above process.    DESCRIPTION OF DRAWING(S) - The figure is a schematic process flow diagram illustrating a process of producing microporous graphite foam.