There’s a new space race to the Moon, and this time the ambitions are not just to visit but to stay. NASA’s Artemis program aims to establish a long-term human presence on the lunar surface in the 2030s. China, India, Japan and a number of private companies all have lunar mission programs of their own.As of now, the human footprint on the Moon is small. That could change with the planned increase of lunar missions.National space agencies are focused on science and exploration, while private companies aim to develop a lunar economy – potentially with mining operations. In the coming years, these groups will test technology and build some initial infrastructure on the Moon. From 2030 onward, Moon bases could become a reality.AdvertisementAdvertisementBut what are the long-term consequences of lunar missions for the Moon itself? The Artemis program’s goals are sustainable exploration and setting up a sustainable presence on the Moon. However, sustainability is a broad concept with a variety of definitions and uses when it comes to space exploration. As a sustainability scholar, a space systems engineer and a planetary scientist, we’ve been trying to pin down what sustainability means in a lunar context.The delicate lunar environmentUnlike Earth, the Moon has no biodiversity, climate as we typically think of it, or oceans. But it does have its own active environment. While the Moon may seem unchanging and indestructible, it is surprisingly sensitive to human activity. Without the wind, water or other natural forces that reshape the Earth, things that happen on the Moon tend to leave a mark – sometimes for thousands, or even millions, of years.When a rocket lands on the Moon, its engines blast the surface with exhaust gases and send fine dust particles flying at enormous speeds. A single landing by a large modern spacecraft, such as SpaceX’s Starship, could disturb an area of the lunar surface two to five times larger than the Apollo missions did in the 1960s and 1970s.Some of those ejected dust particles can travel tens of miles across the surface, and the finest grains can reach the Moon’s orbit, potentially threatening other spacecraft. Images from satellites in lunar orbit show that changes to the uppermost layer of the surface from a single landing can remain visible for decades.AdvertisementAdvertisementLandings can also release water vapor, carbon dioxide and other gases into the lunar exosphere – an extremely thin layer of atoms hovering above the surface – and create a temporary atmosphere.And all these effects can come from just one mission. Future missions will focus on the polar regions, which have ideal spots for collecting solar energy atop peaks, as well as water in the form of ice in craters. Scientists don’t yet understand what the cumulative effects of the dozens of missions planned over the comi …