WASHINGTON — A new report concludes that public-private partnerships, like those NASA has used in its commercial cargo and crew programs, could return humans to the moon for as little as $10 billion and within seven years.

The 100-page study, funded by NASA, concluded that an “evolvable lunar architecture” could eventually lead to a permanent human base at the lunar poles to convert water ice there for propellant that could be sold to NASA or other customers. However, those involved in the study acknowledge that the biggest obstacle to this approach may be convincing policymakers of the plan’s effectiveness.

“We basically say in this study that, in a step-by-step incremental fashion, leveraging commercial partnerships, you can return to the moon. It’s technically feasible,” said Charles Miller, president of NextGen Space, at a July 20 press conference here to unveil the report.

Miller was lead author of the study, supported by a $100,000 contract from the Emerging Space Office of NASA’s Office of the Chief Technologist. Miller prepared the report with a team of veteran NASA officials, and it was reviewed by a 21-person independent review team chaired by former NASA executive Joe Rothenberg.

The report offers a three-phase approach for establishing a permanent human base on the moon. In the first phase, short-term “sortie” crewed missions would land in the moon’s equatorial regions, while robotic spacecraft scouted for sites at the lunar poles most likely to have accessible water ice.

Those sortie missions could be carried out primarily with launch vehicles and spacecraft existing or under development today. The concept described in the report uses SpaceX’s Falcon 9 and Falcon Heavy launch vehicles, Dragon spacecraft and a new lunar lander. An alternative approach, using United Launch Alliance’s Vulcan launch vehicle and Boeing’s CST-100 spacecraft, “is projected to be price competitive” with SpaceX, the report states, but was not studied in detail.

In the architecture’s second phase, human sortie missions would go to the lunar poles, testing technology for extracting ice and converting it into liquid hydrogen and liquid oxygen propellants. The third phase creates a four-person permanent base to oversee production of 200 metric tons of propellant per year.

The report argues the best approach for at least phase one is a public-private partnership similar to what NASA used in for developing commercial cargo and crew transportation systems. Those efforts made use of funded Space Act Agreements rather than conventional contracts, and required companies to contribute funding.

“It’s technically feasible to leverage commercial systems to return to the moon five to seven years from authority to proceed,” Miller said. The estimated cost of achieveing that is $10 billion using two providers, which he said was important to maintain competition and reduce costs. The full cost through completion of the lunar base is about about $40 billion.

Members of the independent review team said they saw no major flaws with the study. “I think it’s very good,” said Christopher Kraft, former director of NASA’s Johnson Space Center, in a pre-recorded video shown at the press conference. He said the study’s projection of a first human landing on the moon within seven years is “very optimistic, but that’s not a bad thing at this point in time.”

“Our group, looking at the economic viability of the plan, found absolutely no showstoppers,” said Hoyt Davidson, managing partner of Near Earth LLC and another member of the review panel. “There are certainly more things that need to be studied, more issues that need to be addressed, but the bottom line is that we saw this as a doable business plan.”

The concept also got a conditional endorsement from Apollo 11 astronaut Buzz Aldrin, who was not involved in the study. He supported its conclusions, but cautioned about taking too many resources from what he believes is the ultimate goal of establishing a human settlement on Mars. “I don’t think we want to get caught in the gravity well of the moon except for commercial activities,” he said, participating in the press conference by phone.

The next step for this concept is unclear, however. Miller said that while NASA is a “tremendous supporter” of the study, any decision to implement its recommendations rests outside the agency.

“It’s the elected leaders of our nation who decide what’s next,” he said. “If the White House and Congress would like NASA to look at taking the next step, I think NASA would be quite responsive.”

The key message of the study, Miller concluded, is that a human return to the moon could cost a fraction of the Apollo program. “We want to want to kill the idea that it has to cost hundreds of billions of dollars to go back to moon,” he said.