Abstract: A lubrication medium supply system and method for delivering lubricant to, for example, the spin bearings of a control moment gyro (CMG), includes a reservoir, a motor, and a valve. A lubrication medium is placed within the reservoir, and the motor, which is coupled to the reservoir, compresses, and thereby pressurizes, the lubrication medium. The valve opens in response to the pressurization of the lubrication medium, to thereby dispense a predetermined amount of lubrication medium from the reservoir, while simultaneously depressurizing the lubrication medium in the reservoir.