On Earth, “we have GPS, and it’s easy to take advantage of that and not think about all the technology that goes into it,” says Alvin Yew, a research engineer at NASA’s Goddard Space Flight Center in Greenbelt, Maryland. “But now when we’re on the moon, we just don’t have that.” Inspired by previous research on lunar navigation, Yew is developing an AI system that guides explorers across the lunar floor by scanning the horizon for distinct landmarks. Trained on data gathered from NASA’s Lunar Reconnaissance Orbiter, the system works by recreating features on the lunar horizon as they would appear to an explorer standing on the surface of the moon. “Because [the moon] has no atmosphere, there’s not a lot of scattering of the light,” says Yew. But by using the outline of the landscape, “we’re able to get a very clear demarcation of where the ground is relative to space.”