The most renowned moon landings are undoubtedly the six Apollo lunar touchdowns, carrying humans to another world for the first time (and still, the only time). However, robotic exploration of the lunar surface in the latter half of the 1960s played a crucial role for those crewed landings and the boot prints that followed. Today, robotics has advanced to the point that landers and rovers operated from Earth provide a capable and cost-effective way to explore the moon.
From research conducted by the Apollo missions, other successful moon landings, dozens of orbiters and powerful telescopes here at Earth, we know more about our one natural satellite than at any point in history. But there is still much to learn. Earlier this year, the Chinese spacecraft Chang’e 4 successfully landed on the far side of the moon. The far side is pocked by ancient craters, mountains and rugged terrain, largely devoid of the smooth maria (basaltic plains) we see on the near side. As more spacecraft reach the far side, planetary scientists able to closely study this alien realm, possibly revealing the history of the moon’s formation along with our own planet’s past. Some even hope to build a radio telescope there, shielded from the radio noise of Earth, to study the most ancient reaches of the universe.
Of the 21 lunar landings, 19—all of the U.S. and Russian landings—occurred between 1966 and 1976. Then humanity took a 37-year break from landing on the moon before China achieved its first lunar touchdown in 2013. Most of those landings occurred near the lunar equator, leaving the poles largely unexplored. With a fleet of new landers and rovers in the works from nations and companies around the world, humans aren’t finished exploring the moon by a long shot.