The scientific objectives of the ExoMars program are defined as follows:
To search for signs of past and present life on Mars;
To investigate the water/geochemical environment as a function of depth in the shallow subsurface;
To study Martian atmospheric trace gases and their sources;
To characterize the surface environment.
The scientific objectives of HABIT are the following:
Investigate the habitability of the landing site in terms of the three most critical environmental parameters for life as we know it: availability of liquid water, UV biological dose and thermal ranges (on Earth, microbial metabolism has only been found above 240 K and reproduction above 255 K);
Provide environmental information (air and ground temperature, ground relative humidity (RH) and UV irradiance), to investigate the atmosphere/regolith water interchange, the subsurface hydration, as well as the ozone, water and dust atmospheric cycle and the convective activity of the boundary layer;
Demonstrate an In-Situ Resource Utilization technology for future Mars exploration.
The clear detection of a high conductivity signal within BOTTLE would reveal that the deliquescence mechanism is in effect on Mars. This would have major implications. First, if would confirm the possibility of a present-day atmosphere-regolith interaction that may lead to the formation of briny mixtures which, in the case of deep slopes may be observed from orbit through large-scale features like Recurrent Slope Lineae. The identification of the transient liquid water and its stability time scales would open the discussion about the possibility of life in present day Mars and various other key points linked with the future human exploration. It is also expected that the demonstration of the formation of liquid brine would have implications on the definition of special regions defined for planetary protection purposes.