I want to know which kind of compressors are best for compressing very cold air. I mean as cold as they can operate in Antarctica during the winter when the temperature will reach around -50°C. In fact, I am looking for compressors that can withstand lower temperature of around -90°C. But, which kind of compressors can perform better in such conditions and where those can be found. One of my friend told me that rotary screw compressors are best and they compress air almost isothermally. But, I want to know whether such compressor can perform similarly even in such cold temperature or not. It may be possible that new kind of problems will arise at such low temperature.