How do you explore Martian caves from millions of miles away? Well, the story of Hansel and Gretel inspired researchers to use... robotic breadcrumbs! Mars is continually blasted by cosmic radiation, which means future crewed mission there will have to recon with appalling surface conditions. But Mars also has lots of subterranean caves, which could provide shelter for human explorers. Problem is, we would need a map of the caves ahead of time to build anything inside of them. Enter: breadcrumb-dropping bots. These robots would explore and map the caves using a mesh-topology network, made of a mother robot connected to a fleet of smaller rovers that explore and map the caves  independently. when they stray too far, they drop a signal-boosting node to keep in touch, so they're constantly sending their data back home. The wireless connection also eliminates the need for the robots to come back for data drop-off, which essentially doubles their range and means we can et better and more complete cave maps. So even fancy space researches can learn something from fairy tales.