The most useful lunar resource map may not come from a high, comfortable orbit. It may come from a spacecraft flying low enough to see the Moon as miners, rover operators, and construction teams will see it: rough, shadowed, uneven, and operationally unforgiving. That was the quiet signal from the 26th Space Resources Roundtable, which wrapped June 5 at Colorado School of Mines. Advanced Space used the meeting to highlight efficient station-keeping of very low lunar orbits , a technical detail that matters because resource prospecting only becomes bankable when orbital data can resolve the terrain, volatiles, slopes, and hazards that surface systems must touch. AI-generated image Very low lunar orbit work turns navigation into a resource prospecting tool. The news: SRR put the Moon’s resource stack in one room SRR XXVI ran June 2 through June 5 in Golden, Colorado. The official program describes record attendance, a record number of presentations, and an unusually broad spread of topics across the Moon, cislunar space, Mars, asteroids, policy, economics, and infrastructure. That is not a launch event, but it is a useful market signal. The lunar resource conversation is getting less theoretical and more operational. The program opened with national and international ISRU updates from NASA, Luxembourg, JAXA, Korea, and the Lunar Surface Innovation Consortium. It then moved into economics, legal frameworks, ethics, prospecting, excavation, regolith handling, oxygen extraction, construction, manufacturing, life support, and orbital sensing. In other words, the conference treated lunar resources as a system, not as a single technology demo. Advanced Space’s June 6 post about the meeting pointed to one of the sharper operational themes: Dr. Jeff Parker’s presentation on Efficient Station-keeping of Very Low Lunar Orbits . The company framed low-altitude orbiting and mapping at the Moon as something that advanced trajectory design and navigation can make practical, helped by low-energy ballistic lunar transfers from Earth to the Moon. Why this matters Very low lunar orbit is not just a path around the Moon. It is a way to close the gap between broad resource maps and decisions about where to land, where to dig, where to build, and what terrain risk is worth taking. 4 Conference days 18 Program sessions 70 Nearly this many Artemis Accords nations cited in the SRR welcome message 1 Main bottleneck: decision-grade lunar data Why very low lunar orbit is hard Low orbit around Earth is familiar because Earth is massive, smooth enough at orbital scale, and surrounded by infrastructure. Low orbit around the Moon is different. The Moon’s gravity field is lumpy. Mass concentrations beneath ancient impact basins disturb spacecraft trajectories. There is no dense tracking network sitting next door. A spacecraft flying close to the surface also has less margin when orbit errors grow. For resource prospecting, that difficulty is also the point. A lower orbit can support sharper sensing, better repeat coverage of target areas, and more useful data for small features near crater rims, shadow boundaries, boulder fields, and landing zones. The south pole is full of operational edge cases. Permanently shadowed regions may hold volatiles, but nearby ridges can offer more sunlight and communications opportunities. The most valuable sites may sit near the most awkward terrain. Efficient station-keeping is the act of keeping the spacecraft where the mission needs it without spending propellant too quickly. For a very low lunar orbiter, every meter per second matters. Too much correction burns lifetime. Too little correction lets the spacecraft drift away from the observing geometry that made the mission valuable in the first place. AI-generated image Prospecting becomes more useful when orbital data can resolve terrain at the scale surface systems need. The low-orbit trade • Better data: Lower altitude can improve imaging geometry, sensing resolution, and repeat observations of high-value sites. • Higher operations burden: Orbit maintenance, navigation, and tracking become more demanding. • Shorter margin: Small errors matter more when the spacecraft is close to irregular terrain. • Resource payoff: The data can narrow where prospectors, excavators, power systems, and landing pads should go first. The resource economy needs maps it can trust The SRR program shows how many pieces now depend on better lunar ground truth. Presentations covered radar mapping, infrared spectroscopy for subsurface water ice, neutron counting, gamma-ray and neutron spectrometer calibration, volatile loss during excavation, icy highlands regolith simulants, oxygen extraction, lunar operating guidelines for infrastructure, and surface construction. That list is a warning: the lunar resource economy is data hungry before it is hardware hungry. Broad maps can identify promising regions. They cannot by themselves tell a company whether a specific lander can touch down safely, whether a rover can cross a slope, whether an excavator will lose volatiles during handling, or whether a berm, pad, cable run, or power tower belongs in one patch of regolith rather than another. The Moon is not a flat test range. It is a hostile construction site with bad lighting, abrasive dust, thermal extremes, and limited rescue options. That is why the orbital layer matters. A very low lunar orbiter can sit between global reconnaissance and local operations. It can revisit candidate sites, refine hazard models, collect higher quality observations, and feed planning tools before mass is committed to the surface. For ISRU, this is especially important because extraction systems are not useful if they arrive at the wrong grade of material, the wrong terrain, or the wrong thermal environment. Need Why low lunar orbit helps Water ice prospecting Sharper repeat observations can improve confidence around polar cold traps and nearby access routes. Landing site selection Closer passes can support better hazard awareness for slopes, boulders, crater rims, and shadow boundaries. Construction planning Surface preparation, berms, pads, roads, and utilities need terrain data at useful engineering scales. Commercial diligence Investors and customers need resource estimates that are tied to reachable sites, not just promising regions. Advanced Space has a reason to push this angle Advanced Space is not entering this discussion cold. The company operated CAPSTONE, the small NASA-funded spacecraft that tested the near-rectilinear halo orbit planned for Gateway. CAPSTONE gave Advanced Space direct experience with cislunar mission design, navigation, operations, and lunar transfers. The SRR program also notes the company’s focus on cislunar communication, navigation, timing, and mapping to support NASA’s lunar initiative and future Moon Base work. That background makes the very-low-orbit topic more than an academic exercise. If the Moon is going to host repeat landings, resource prospecting, construction experiments, and commercial payloads, then navigation and mapping become shared infrastructure. They do not look as dramatic as a lander plume or a rover deployment, but they decide whether those systems can work together. Low-energy ballistic lunar transfers add another practical layer. These trajectories can reduce propellant needs by using the Earth-Moon-Sun gravitational environment, though they often take longer than direct transfers. For smaller spacecraft, the trade can be attractive. If a low-cost orbiter can reach the Moon efficiently, then spend its propellant carefully in a low mapping orbit, the economics of focused resource reconnaissance improve. AI-generated image Low-energy transfers can make small lunar reconnaissance missions more propellant efficient, at the cost of time. SRR’s bigger message: resource work is turning into infrastructure work The most revealing part of SRR XXVI is the mix. One session covered DARPA’s Lunar Assay