ANITA2 Trace Gas Analyser for the ISS - Flight Model Finalization and ground test results
The ANITA2 (Analysing Interferometer for Ambient Air) instrument is a trace gas analyser, designed to operate onboard the ISS and to monitor the cabin atmosphere. Within the last 2 years, significant progress has been made towards realizing the flight instrument, including the flight-like design, manufacturing, and functional testing of the opto-mechanical components, as well as further development of the gas analysis methods. ANITA2 will deliver information on the air conditions, analysing in parallel more than 30 of the most important trace gases in the cabin atmosphere. The advantages of the ANITA type instruments include high sensitivity, accuracy, precision and time resolution of the measurement data, as well as no consumption except electrical power and no production of waste. The novel, sophisticated analysis software is further improved, employing statistical and non-linear calibration and analysis methods. Thus, detailed, continuous, and quasi real time information on the cabin air quality becomes available. ANITA2 is also a stepping stone into the future, as a precursor system for crewed stations, bases, and exploration missions (Gateway, Moon, Mars...) where bringing local gas samples to earth for analysis is not feasible. Therefore the availability of local gas analysis capabilities for a wide range of substances is a key requirement. The paper gives an overview of ANITA2. This includes the overall system concept and design as well as details about sub-systems. The current Optical Breadboard is shown and described, which contains all opto-mechanical components of ANITA2 in a flight-like design. In addition, the main results of the very successful performance testing of the Optical Breadboard are presented. These tests showed a robust, high optical quality at various conditions. ANITA2 has successfully passed PDR in June 2018 and will be ready for flight and start-up on the ISS in 2020. The Flight Model manufacturing started beginning of 2019.