ExoMars is an Italian-led ESA dual mission carried out in collaboration with the Russian space agency Roscosmos, with the goal of investigating traces of past and present life on Mars and geochemical characterization of the planet. The first mission-the Trace Gas Orbiter (TGO)-was launched in 2016 while the second, which includes a rover and a surface platform, is planned for 2022. Together they will address the question of whether life ever existed on Mars.

In fact, the second mission consists of an innovative rover, called Rosalind Franklin, capable of exploring Mars and penetrating the surface to analyze it. Italy, through ASI, is the main supporter of the dual ExoMars mission with 40 percent of the total investment.

ExoMars2022 will land on Mars in the Oxia Planum region, located at the eastern edge of the Chryse Basin at the exit of the Coogoon Valles system. Oxia Planum contains one of the largest exposures of rocks on Mars dated to about 3.9 billion years old and rich in clay, indicating that water once played an important role here. In order to maximize the chances of finding signs of past life on Mars, it is indeed necessary to target the “sweet spot” in the geologic history of Mars, that is, to look at the beginning of the Noachian era and look for vast areas that preserve evidence of low-energy, water-rich environments. The rocks appearing in the area of the landing site have different compositions. In addition, remnants of an ancient period of volcanic activity may have been preserved beneath the surface, protected from radiation and oxidation by the planet, and exposed to erosion only in the last few hundred million years.

The European rover will be the first mission to combine the ability to move on the surface and study Mars in depth. ExoMars will have a nominal lifetime of about 7 Earth months, during which it will provide mobility of several kilometers by relying on electricity from solar panels.

ESA’s Rover has some key capabilities for the dual ExoMars mission: surface mobility, subsurface drilling and automatic sample collection, processing and distribution to the various instruments. It houses a set of instruments, known as the Pasteur payload, dedicated to exo-biology and geochemical research.

• PanCam (panoramic camera): two wide-angle stereo cameras and a high-resolution camera to study the rover environment and the geology of the landing site. Also very important for target selection and rock texture studies.
• ISEM: IR spectrometer for characterization of bulk mineralogy, identification of water-bound minerals, and to aid PanCam in target selection.
• WISDOM radar (observations of water, ice and subsurface deposits on Mars): to establish subsurface stratigraphy down to 3 m depth and help plan drilling strategy.
• ADRON (active gamma-ray and neutron detector): subsurface neutron detector to determine the subsurface hydration level and the possible presence of an ice fraction at 1 m depth.
• CLUPI (Close-up Imager): to study rock targets at close range (50 cm) with sub-millimeter resolution. This instrument will also analyze image samples collected by the drill during drilling operations. The close-up imager has variable focus and can obtain high-resolution images even at longer distances. Some morphological biosignatures, such as biolamination, if present, can be identified by CLUPI.
• Ma_MISS: IR spectrometer on the drill suitable for conducting mineralogical studies in the borehole walls.
• Underground borehole: 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).
• SPDS (Sample Preparation and Dispensing System): receives a sample from the drilling system, produces particulate material preserving organic and aqueous fractions, and presents it to all laboratory instruments. Includes a dispenser with additional blank samples.
• MicrOmega (Micro observatoire pour la mineralogie, l’eau, les glaces et l’activite ́): VIS+IR imager spectrometer that will examine the crushed sample material to characterize its structure and composition at the particle size level. These measurements will be used to help target laser-based instruments (RLS and MOMA).
• RLS (Raman Laser Spectrometer): aimed at identifying grain-scale mineral phases in the crushed sample, determining their composition and establishing the presence of carbon (inorganic/organic).
• MOMA (LD + Der-TV GCMS): the Mars organic molecule analyzer is also the rover’s largest instrument. Its goal is to conduct a wide-ranging, very high-sensitivity search for organic molecules in the collected sample. It includes two different ways of extracting organics: (1) LD (laser desorption) and (2) TV (thermal volatilization), with or without derivatization agents (Der). Identification of evolved organic molecules is achieved with an MS ion trap.