Digging Deeper to Find Life on Ocean Worlds - NASA Science
First, the heart of a cryobot is a nuclear power system that generates the sustained heat required to melt through kilometers of ice. Various nuclear power systems that could suit a cryobot system have been identified, including the familiar Radioisotope Power Systems (RPS) that have powered many deep-space missions, and fission reactors that may be developed in the coming years. Two key constraints that drive the power system design are: (1) sufficient total power and density to facilitate efficient melting (about 10 kW), and (2) integration within a structural vessel to protect the power system from the high pressures of the deep ocean. These challenges are both solvable and have some historical precedent: NASA’s Cassini mission had a 14 kW thermal power system, and several Radioisotope Thermoelectric Generators (RTGs) were deployed to the bottom of the ocean in the 1960s and 1970s as power sources for navigation beacons, which operated in comparable pressures to the Europan ocean. However, a cryobot power system will require a concerted effort and close collaboration with the Department of Energy throughout the maturation of the mission concept.