A small, low power, low maintenance sensor for monitoring air quality in human exploration and planetary habitats is being developed.. The sensor is based on the technologies of a focal plane mass analyzer, and an array detector. It is a nonscanning type of mass spectrometer measuring signals at all masses simultaneously. It will possess high sensitivity (ppb concentration levels). The miniature mass spectrometer (MMS) can also be used for chemical and isotopic analysis of planetary atmosphere, and surface /rock materials. MMS, when fully developed, will weigh 0.5 - 0.7 kg and consume ∼ 1 W of power.