In this paper we report on a reliable, small, efficient, low power, vibrationally balanced pulse tube cooler designed specifically for use on small satellites. The pulse tube cooler reliability derives from the absence of cold moving parts.The vibrationally balanced, miniature, integral pulse tube cooler, intended for a 10-year long-life space application, incorporates a nonwearing flexure bearing compressor vibrationally balanced by a motor-controlled balancer and a completely passive pulse tube cold head. Cooler weight is 2.0 kg. The maximum cooling power measured at 80 K is 800 mW for an input power to the compressor of 30 watts. The cooler is suitable for cooling sensors and optics between 60 K and 200 K, with powers up to 3.5 watts at 200 K. Self-induced vibration measurements indicate that the cooler can be balanced to reduce vibration forces below 0.02 newtons (N) from 0 to 1000 Hz. The first flight is scheduled for 1996.