Human Health and Performance
Monitor how astronauts respond physically and psychologically to living and working on the lunar surface, helping build the knowledge needed for longer missions farther from Earth.
The lunar surface preserves a record more than 4.5 billion years in the making. Revealing that story will require exploration across the Moon: from ancient impact basins and volcanic landscapes to environments that offer entirely new ways to observe the Universe.
At the request of NASA, Human Exploration Across the Moon identifies high-value science destinations for short-duration human missions beyond the lunar poles. This report charts a path toward broader exploration, presenting four non-polar destinations where human explorers could pursue distinct and complementary science objectives across a range of disciplines: Bhabha Crater, Mons Hadley, Orientale Basin, and Aristarchus Plateau.
Science Across the Moon
The Moon is not one uniform landscape. Different regions offer unique glimpses into lunar history and different environments for discovery. Ancient impact basins can help reconstruct the early history of the Solar System. Volcanic terrains preserve evidence of the Moon’s interior and evolution. The far side offers a radio-quiet environment for astronomy, while near-side locations provide vantage points for continuous observations of cislunar space and geospace.
Exploring across these different environments can also build a more complete picture of the Moon itself. Measurements repeated at multiple landing sites can reveal how its interior, surface, radiation environment, regolith, and other conditions vary across the lunar body. Together, the four recommended destinations enable distinct and complementary investigations—and, collectively, planet-scale science.
Four Destinations Across the Moon
Bhabha Crater, Mons Hadley, Orientale Basin, and Aristarchus Plateau – these four destinations were selected to maximize the scientific and exploration return possible from short-duration human missions to non-polar regions of the Moon. Each provides access to a different part of the Moon’s history and a different set of opportunities for future exploration.
Science at Every Landing Site
Some high-priority investigations can benefit from being carried out wherever humans land on the Moon. Repeating these measurements across different lunar environments can build a more complete picture of the Moon and strengthen the knowledge needed for future exploration. Not every investigation would necessarily be carried out on every mission, but each can contribute valuable measurements wherever humans land.
Environmental Monitoring
Deploy environmental and geophysical instruments to measure conditions on the lunar surface and within the Moon, contributing to a broader understanding of its interior and external environment and providing critical context for scientific measurements and operations.
Regolith Collection
Collect lunar soil from different environments for geological and biological research, studies of human health hazards, and investigations of how lunar materials might be used as resources.
Moon Design Handbook
Gather empirical data from real lunar operations to improve the design and operation of future surface systems, infrastructure, vehicles, and mission activities.
Space Domain Awareness
Use the Moon as a stable platform to observe cislunar space for space traffic management, planetary defense, space-weather awareness, and other applications.
Expanding What is Possible
The report's four sorties were designed to demonstrate that compelling science can be accomplished using near-term capabilities. Each mission is baselined without a crewed rover and with astronauts remaining within 2 kilometers of their lander. No sortie depends on extensive prepositioned surface infrastructure.
But the report also identifies capabilities that would either expand the science possible or are necessary to plan and carry out the missions as described.
- Explore Farther
The current 2-kilometer maximum exploration distance limits the locations and scientific targets astronauts can reach. Increasing that distance safely would provide more flexibility in landing-site selection and allow more science to be accomplished during each mission.
A simple unpressurized rover would likewise expand the reach of every sortie by reducing travel time and fatigue, increasing carrying capacity, and making instrument deployment more efficient. The report concludes that valuable science can be accomplished without a rover, but mobility would significantly increase the return.
- Maintain a View from Orbit
Continued high-resolution orbital reconnaissance is needed to identify hazards, map scientifically valuable targets, support navigation and select locations for sampling and instrument deployment. The report calls for a successor to the Lunar Reconnaissance Orbiter to maintain this capability.
- Keep Science Running Through the Lunar Night
Astronauts would not remain at these sites through the lunar night, but many instruments they deploy are intended to operate long after the crew leaves. Those instruments need to survive and operate over repeated lunar day-night cycles and extreme temperature changes to maximize scientific return.
- Stay Connected
Human explorers require continuous communications while operating on the surface. Missions to the lunar limb and far side require additional communications capabilities, while systems supporting Bhabha must also preserve the far side's valuable radio-quiet environment.
- Bring the Science Home
Returned samples and data require long-term support on Earth. The report calls for continued sample curation, laboratories, scientific facilities and a trained workforce capable of extracting scientific value from material returned by future lunar missions.
Sending Human Explorers to the Moon
The report frames the question not as whether humans or robots should explore the Moon, but how their different capabilities can be used together most effectively to maximize scientific return.
Robotic systems can perform reconnaissance before astronauts arrive, scout difficult or hazardous terrain, carry equipment, collect repetitive measurements, and continue observations after astronauts leave. They can reduce risk and extend the reach of human exploration.
Human explorers bring different capabilities. Astronauts can assess an unfamiliar environment, recognize unexpected features, change plans in real time, make geological judgments in the field, select the most valuable samples, maximize sample return mass, and install or adjust complex scientific equipment.
FAQ
- How are the landing sites prioritized?
The four destinations are prioritized according to their ability to address decadal-level science objectives, advance exploration capabilities, and provide compelling reasons for exploration. That priority order is not necessarily the order in which missions should occur; sequencing depends on mission experience, communications capabilities, and technological readiness.
- What is a lunar sortie?
For this report, a sortie is a short-duration surface mission with two astronauts and one to four extravehicular activities (EVAs). The notional missions presented in the report are used to demonstrate that the recommended science is feasible at that scale; they are not prescriptions for the exact spacecraft, instruments, or mission design that NASA must use.
- Can some science objectives be accomplished at more than one landing site?
Some objectives require a specific destination, while others require characteristics found at several non-polar sites. The report identifies optical interferometry, space-weather monitoring, gravitational-wave astronomy, and regolith shielding as “site-flexible” objectives and recommends preferred locations based on scientific return and feasibility.
- How do these missions relate to exploration of the lunar South Pole?
The report treats non-polar exploration as complementary to sustained polar exploration. The South Pole offers important opportunities, including access to permanently shadowed regions and potential water ice, while non-polar sites provide access to geological environments, astronomical vantage points, space-weather observations, and other science that cannot all be accomplished from the poles.
- Do these missions require infrastructure to already be in place on the lunar surface?
Not extensive surface infrastructure. The report deliberately baselines the sorties without crewed mobility or extensive pre-positioned assets so that significant science can be achieved with relatively near-term capabilities. Some supporting capabilities are still necessary, however—particularly orbital reconnaissance, communications, and the ability for deployed instruments to survive lunar day-night cycles.