In low light level environments (LLEs) on Earth, humans typically provide sufficient, if not excessive, illumination via abundant energy sources. Planetary surface rovers have extensively explored exclusively in the sunlight. However, robotic exploration in LLEs of interest to resource potential, e.g. permanently shadowed regions at lunar poles, or biologically protective environments, e.g. lava tubes and other caves, share a common characteristic; abundant energy is seldom, if at all, available. Anyone that has traveled in the dark is aware of how their perception of their surroundings is driven by their illumination source. We discuss the potential impact on science operations and understanding that occurs while operating a rover in LLEs.
