The Mars Organic Molecule Analyzer (MOMA) Instrument: Characterization of Organic Material in Martian Sediments

Abstract

The Mars Organic Molecule Analyzer (MOMA) instrument onboard the ESA/Roscosmos ExoMars rover (to launch in July, 2020) will analyze volatile and refractory organic compounds in martian surface and subsurface sediments. In this study, we describe the design, current status of development, and analytical capabilities of the instrument. Data acquired on preliminary MOMA flight-like hardware and experimental setups are also presented, illustrating their contribution to the overall science return of the mission. Key Words: Mars—Mass spectrometry—Life detection—Planetary instrumentation. Astrobiology 17, 655–685. 1. Introduction: The Mars Organic Molecule Analyzer (MOMA) Investigation 2. Science Goals 3. Objectives and Requirements 4. Instrument Top-Level Description 5. Instrument Development 5.1. Team organization 5.2. Instrument integration flow 5.3. Instrument verification 5.4. Achieved milestones and deliveries 6. Instrument Subsystems 6.1. Oven and tapping station subsystems 6.1.1. Derivatization 6.1.1.1. MTBSTFA 6.1.1.2. DMF-DMA 6.1.2. Thermochemolysis 6.1.3. Wet chemistry: storage and release of chemical agents 6.2. Gas chromatograph subsystem 6.2.1. Design requirements 6.2.2. Design overview 6.2.2.1. General architecture 6.2.2.2. Injection system 6.2.2.3. Separation of volatiles 6.2.2.4. Detection of volatiles 6.2.2.5. Gas handling system 6.2.2.6. GCMS coupling campaigns 6.3. Laser subsystem 6.3.1. Design requirements 6.3.2. Laser architecture 6.3.3. Verification data 6.4. Mass spectrometer subsystem 6.4.1. Design requirements 6.4.2. Analyzer architecture 6.4.2.1. Linear Ion Trap assembly 6.4.2.2. Detection channels 6.4.2.3. Electron Ionization Source 6.4.2.4. Fast-actuating aperture valve 6.4.2.5. Micropirani pressure sensor 6.4.2.6. Wide-Range Pump 6.4.3. Temperature control 6.4.4. Driving electronics 7. Operation of MOMA on the Surface of Mars 7.1. Expected measurement scenarios 7.2. Sequenced operational modes 7.3. Synergy with other instruments 7.3.1. Data interpretation 7.4. LDMS operations on Mars and test experiments on LDMS prototype system 7.5. Test experiments on GCMS prototype system: a case study 7.5.1. Sample and setup 7.5.2. Methods 7.5.2.1. Stepwise pyrolysis 7.5.2.2. Derivatization/thermochemolysis 7.5.2.3. GCMS parameters 7.5.3. Results and discussion 7.5.3.1. Pyrolysis 7.5.3.2. Derivatization and thermochemolysis 8. Discussion 9. Summary Acknowledgments Author Disclosure Statement References Abbreviations Used