1. Historical Context and Detailed Objectives

The ExoMars program addresses the lack of deep sampling capacity in the Martian record. The fundamental objective is the in situ search for chemical biomarkers preserved from UV and GCR radiation degradation. The mission seeks to determine if life existed or persists in the subsurface, analyzing mineralogical and organic composition at depths of up to two meters.

2. Vehicle Architecture and Main Subsystems

The rover has a mass of ~310 kg, with a "triple-bogie" locomotion system. Thermal control integrates radioisotope heater units (Pu-238 LWRHUs and Am-241 RHUs) to maintain the Warm Electronics Box (WEB). Power is provided by photovoltaic solar panels, with a load capacity of 1200 Wh/sol and a 1142 Wh lithium-ion battery.

3. Payload and Scientific Instrumentation

The "Pasteur Payload" includes:

• PanCam: Stereo and multispectral system for mapping.
• Enfys: Near-infrared spectrometer (0.9-3.2 µm) for mineralogical analysis.
• WISDOM: 500 MHz-3 GHz GPR for subsurface structure detection.
• MOMA: Organic molecule analyzer via Py/GC-MS and LD-MS with a Linear Ion Trap (LIT).
• RLS: Raman spectrometer (532 nm) for molecular identification.

4. Launch Vehicle and Flight/EDL Profile

The transit utilizes a Hohmann/Lambert-type trajectory. The EDL profile includes: hypersonic entry (ablative aeroshell), deployment of DGB (Disk-Gap-Band) parachutes in the supersonic regime, and a propulsive landing phase using throttleable engines provided by NASA for a touchdown at speeds below 3 m/s.

5. Operational Development and Scientific Results

The selection of Oxia Planum, characterized by Noachian hydrated phyllosilicates, maximizes the probability of finding prebiotic environments preserved under the caprock unit. The rover is designed for operational autonomy based on relay transmission via the Trace Gas Orbiter (TGO) in the UHF band.

6. Conclusion and Technical Legacy

ExoMars establishes a paradigm in astrobiology by prioritizing stratigraphic preservation. The use of Am-241 and deep drilling techniques position this mission as the technological benchmark for characterizing exobiological environments in the outer and inner solar system.