Could lava tubes, caves, or subsurface habitats offer safe refuge for future astronauts on Mars? Scientists with NASA’s Curiosity Mars rover team are helping explore questions like that with the Radiation Assessment Detector, or RAD.

Unlike Earth, Mars doesn’t have a magnetic field to shield it from the high-energy particles whizzing around in space. That radiation can wreak havoc on human health, and it can seriously compromise the life support systems that Mars astronauts will depend on, as well.