During the entry of the EDL demonstrator in the Martian atmosphere, the module is surrounded by a heat plasma. The characterization of this gas and his radiative property are key parameters for the Thermal Protection Shield (TPS) design.
The prediction of the radiative heat flux on the Mars space vehicle's surface relies at the same time on numerical simulations and on several models (mainly optical models and chemical-kinetic models). On the space vehicle back-shield, the radiative heat flux can represent up to 100 % of the total heat flux. This flux is mainly due to the infrared radiation of CO2 and CO for low/medium Mach numbers. In order to verify the theoretical computations, the space vehicle will be instrumented.
The first mission within the ESA - Roscosmos ExoMars Programme, scheduled to arrive at Mars in 2016, consists in an Orbiter plus an Entry, Descent and Landing Demonstrator Module (EDM).
The ESA-led Orbiter will perform detailed, remote observations of the Martian atmosphere, searching for evidence of trace gases of possible biological importance, such as methane and its degradation products. Instruments onboard the Orbiter will carry out a variety of studies, including:
- Highly sensitive measurements of trace gases from which the composition of the atmosphere can be determined. This will provide important clues to the possible origin of the gas source, for example, is it of volcanic or biogenic origin?
- The measurement and low-resolution imaging of aerosols in the atmosphere, investigation of the temperature variations in the atmosphere, and the mapping of key trace gas species other than methane.
- High-resolution imaging of gases in order to provide the geological context, if it exists, for sources that have been identified.
The payload will include European and Russian instruments.
The second mission scheduled to arrive at Mars in 2021, will deploy a rover on the surface of Mars.
The science objectives of the ExoMars Rover, in order of priority, are:
- To search for signs of past and present life on Mars;
- To characterise the water/geochemical environment as a function of depth in the shallow subsurface.
The ExoMars Rover mission will pursue one of the outstanding questions of our time by attempting to establish whether life ever existed, or is still active on Mars today. The Rover will carry a comprehensive suite of analytical instruments dedicated to exobiology and geochemistry research: the PASTEUR payload. The Rover will travel several kilometres searching for signs of past and present life, collecting and analysing samples from within rocky outcrops and from the subsurface, down to a depth of 2 m.
The landing platform will transport the Rover and a stationary scientific payload package to the surface of Mars. It will provide the means for the Rover to disembark (egress) to begin its mission on the surface of Mars. Once the Rover has completed its egress the Landing Platform will become a science station operated by Roscosmos with cooperation from ESA.