In this challenge, participants are invited to design a mission scenario for exploring the deep subsurface of a planetary crust — several kilometres below the surface — where life may survive under extreme conditions. Analogous environments on Earth, such as deep mines, geothermal boreholes, or oceanic basaltic rocks, provide valuable insights into potential habitats on Mars, Europa, Enceladus, or Ganymede.

The challenge is to develop a robotic subsurface exploration mission (either as an Earth-based analogue experiment or as a future space concept) with the goal of detecting evidence of life — active or dormant. Particular emphasis should be placed on safe and effective drilling methods, strict contamination control, and reliable sample analysis in extreme, lightless, and energy-limited environments subjected to high pressure.