Table 1.
The ExoMars Rover's Pasteur Payload Can Perform a Detailed Mineralogical and Chemical Characterization of Surface and Subsurface Material Collected with the Drill
| Instrument | Scientific rationale |
|---|---|
| Panoramic instruments | To characterize the rover's geological context, both at the surface and the subsurface. Typical scales span from panoramic (100 m) to 1 m, with a spatial resolution in the order of 1 cm for close targets. |
| Panoramic camera system | PanCam: Two wide-angle stereo cameras and one high-resolution camera to investigate the rover's environment and landing site geology. Also very important for target selection and for rock textural studies. |
| IR spectrometer | ISEM: For bulk mineralogy characterization, remote identification of water-related minerals, and for aiding PanCam with target selection. |
| GPR | WISDOM: To establish subsurface stratigraphy down to 3 m depth and help plan the drilling strategy. |
| Neutron detector | ADRON: To determine the level of subsurface hydration and the possible presence of an ice fraction to 1 m depth. |
| Contact instruments | To investigate outcrops, rocks, and soils. Among the scientific interests at this scale are macroscopic textures, structure, and layering. This information will be fundamental to understand the local depositional environment and to search for morphological biosignatures on rocks. |
| Close-up imager | CLUPI: To study rock targets at close range (50 cm) with sub-millimeter resolution. This instrument will also investigate the fines produced during drilling operations, and image samples collected by the drill. The close-up imager has variable focusing and can obtain high-resolution images also at longer distances. Certain morphological biosignatures, such as biolamination, if present, can be identified by CLUPI. |
| IR spectrometer in drill | Ma_MISS: For conducting mineralogical studies in the drill borehole's walls. |
| Support subsystems | These essential devices are devoted to the acquisition and preparation of samples for detailed studies in the analytical laboratory. The mission's ability to break new scientific ground, particularly for “signs of life” investigations, depends on these two subsystems. |
| Subsurface drill | Capable of obtaining samples from 0 to 2 m depth, where organic molecules can be well preserved from radiation damage. Includes a blank sample, temperature sensors, and an IR spectrometer (Ma_MISS). |
| Sample preparation and distribution system | Receives a sample from the drill system, produces particulate material preserving the organic and water fractions, and presents it to all analytical laboratory instruments. Includes a dispenser with additional blank samples. |
| Analytical laboratory | To perform a detailed, coordinated analysis of each collected sample. After sample crushing, the initial step is a visual and spectroscopic investigation. Thereafter follows a first search for organic molecules. In case interesting results are found, the instruments are able to perform more in-depth analyses. |
| VIS + IR imaging spectrometer | MicrOmega: Will examine the crushed sample material to characterize structure and composition at grain-size level. These measurements will be used to help point the laser-based instruments (RLS and MOMA). |
| Raman laser spectrometer | RLS: To identify mineral phases at grain scale in the crushed sample material, determine their composition, and establish the presence of carbon (inorganic/organic). |
| Mars organic molecule analyzer | MOMA (LD + Der-TV GCMS): MOMA is the rover's largest instrument. Its goal is to conduct a broad-range, very-high sensitivity search for organic molecules in the collected sample. It incudes two different ways of extracting organics: (1) LD and (2) TV, with or without derivatization (Der) agents, followed by separation using four GC columns. The identification of the evolved organic molecules is achieved with an ion trap MS. |
ADRON, active detector for gamma rays and neutrons; CLUPI, close-up imager; GC, gas chromatograph; GPR, ground-penetrating radar; IR, infrared; ISEM, infrared spectrometer for ExoMars; LD, laser desorption; Ma_MISS, Mars multispectral imager for subsurface studies; MOMA, Mars organic molecule analyzer; MS, mass spectrometer; RLS, Raman laser spectrometer; SPDS, sample preparation and distribution system; TV, thermal volatilization; WISDOM, water, ice, and subsurface deposit observations on Mars.