The development of HABIT (HAbitability, Brines, Irradiation and Temperature) instrument can be considered the cardinal project of those carried out by the Group of Atmospheric Science. HABIT is designed to study one of the most outstanding discoveries of NASA’s Curiosity rover, operating on Mars since August 2012: the presence of transient liquid water on Martian ground as part of a daily water exchange between soil and atmosphere.
The core goal of HABIT is to verify the occurrence of this phenomenon, which has been inferred from indirect analysis of data, and whose implications in the present and future exploration of Mars have long reach in several aspects.
First, it poses a novel approach for the understanding of the Martian environment regarding the dynamics of the surface, the atmospheric boundary layer, and their interactions through the interface. For instance, the formation of liquid brines in the regolith has provided the best way to explain the so call Recurrent Slope Lineae (RSL), which have been widely registered on different inclining features all over Mars, to mention just an example.
Second, it is of the utmost importance for assessing the present habitability of Martian surface, one of the fundamental scientific objectives of the whole ExoMars Programme.
Liquid water seems to be an essential requirement for life (as we know it), so its presence in present day Mars opens the possibility that, if life arose there sometime in the distant past, when there were oceans on its surface, it had survived in certain environments where water is still available.
On the other hand, the presence of liquid water poses the necessity of maximizing the cautions to avoid the contamination with terrestrial organisms (spacecrafts bioburden), which could also find favourable conditions to thrive.
Finally, through the investigations of the water cycle, HABIT will serve as a test of the technology which could eventually be used as a means to gather water, an invaluable resource for the future manned mission to Mars, which are in the middle term horizon of the space agencies exploration programmes.
HABIT project is being developed at Luleå Tekniska Universitet by the Group of Atmospheric Science, under the sponsorship of the Swedish National Space Board (SNSB), and with the collaboration of the space company OMNISYS. It will be part of the ExoMars 2020 mission scientific payload and, in particular, it will be mounted on the Surface Platform, the Russian module provided by the Russian Space Agency ROSCOSMOS in the frame of the collaboration with European Space Agency in the ExoMars Programme.
ExoMars is an ambitious programme scheduled by the European Space Agency (ESA) in collaboration with the Russian Space Agency ROSCOSMOS, with the main goal of ascertaining if life ever existed on Mars, while going into depth in the investigation of Martian environment. It is composed of two successive missions, namely ExoMars 2016 and ExoMars 2020.
ExoMars 2016 consists of an orbiter, the Trace Gas Orbiter (TGO) and the “Schiaparelli” Entry, Descent and Landing Demonstrator (EDM). This latter’s main objective was to test the technology that will allow to land the ExoMars 2020’s rover and Surface Platform. TGO inserted into its initial orbit around Mars successfully on 19th October 2016. It will only be fully operative after completing a long series of complicated aerobraking manoeuvres to reach its definitive circular orbit around the planet by at the end of 2017.
ExoMars 2020 consists of a Surface Platform and the 2020 Rover, the cornerstone of the programme. The rover will reach Mars’ ground “wrapped” by a structure that constitutes the second module of this mission, the Surface Platform, which will be deployed to release the rover once the landing stage is completed. Then, the rover will travel several kilometres during the mission taking samples of the subsurface from a depth of up to two meters, since it is below the surface where it is more likely to find the biomarkers it will look for.
As for the Surface Platform, it will stay stationary at the landing point gathering environmental measurements with its science payload, among which HABIT is included.