It is one of the most spectacular reports in current space research: the data from NASA's InSight probe suggest the urgent conclusion that a gigantic water reservoir lies dormant beneath the surface of Mars! In fact, the reservoir could even be large enough to flood the entire planet one to two kilometers high! The cool water is hidden in the cracks and pores of the Martian crust - and according to the experts, it is even possible that Martian life is still slumbering down there!