WASHINGTON — With growing bipartisan skepticism that NASA’s current plan to return humans to the moon by 2024 is achievable, members of the House Science Committee used a Nov. 13 hearing to advocate for a different, and arguably more conventional, approach.

In statements at a hearing of the committee’s space subcommittee on human exploration of the moon and Mars, both top Democratic and Republican members of the committee said they doubted NASA’s current approach to get back to the moon within five years under the Artemis program was achievable, but for different reasons.

“I support a robust program of exploration that leads to Mars, but it needs to be one that is sustainable,” said Rep. Eddie Bernice Johnson (D-Texas), chair of the committee, in her opening statement. “Unfortunately, based on the limited information provided to date, the administration’s 2024 lunar landing directive appears to be neither executable nor a directive that provides a sustainable path to Mars.”

“An arbitrary deadline that is uninformed by technical and programmatical realities, that is unaccompanied by a credible plan and that fails to identify the needed resources is one that sets NASA up to fail rather than enabling it to succeed,” she continued.

Her comments came moments after an opening statement by the subcommittee’s ranking member, Rep. Brian Babin (R-Texas), whose doubts were instead based on a lack of funding secured for the Artemis program in 2020 spending bills and skepticism from members of a House appropriations subcommittee at an Oct. 16 hearing.

“At our last space subcommittee hearing, NASA said that maintaining the 2024 date for a lunar landing is unlikely if they do not receive the additional funding that they requested in their budget amendment,” he said. “If a recent House Appropriations Committee hearing is any indication, the likelihood of receiving additional funding this year is dwindling.”

Babin said that such a shortfall could have the benefit, from his perspective, of forcing NASA to reevaluate its current approach to returning to the moon. “If this forces NASA to reassess its schedule for returning to the moon, it would provide an opportunity to ensure that they are developing the ideal architecture that maximizes mission success and minimizes risk,” he said. “This could be done by developing landers that leverage the investments already made by the taxpayers in national capabilities like SLS and Orion.”

Babin and other Republican members of the subcommittee used the hearing to raise questions about NASA’s current approach, which makes extensive use of commercial launch vehicles to launch elements of the lunar Gateway and lunar landers, in favor of one that uses the SLS to launch lunar landers, perhaps without using the Gateway at all.

The hearing’s two witnesses supported those arguments. “The mission I did accomplished the whole thing with one launch,” said Tom Stafford, a retired astronaut who flew to the moon on Apollo 10, the “dress rehearsal” for the Apollo 11 landing, in 1969. Stafford cited testimony at a previous subcommittee hearing by Doug Cooke, a former NASA official, critical of NASA’s current approach. “The probability of success as he outlined, and I cannot disagree with it, was only 50%. I would certainly not want to start that.”

A heavy-lift rocket like the SLS was essential, Stafford said. “If you don’t have a big booster, you’re not going to make it,” he said. A large rocket also offers a larger volume that can accommodate rovers and other infrastructure needed for lunar exploration. “You have to have a big shroud, which leads you to a big, wide-diameter booster. If you don’t have it, you’re not going to make it.”

The hearing’s other witness, former NASA center director and aerospace executive Tom Young, argued that NASA needed to return to more conventional ways of managing the exploration program. He called for augmenting NASA’s “leadership capabilities” and workforce and using more standard contracting approaches.

“Managing and contracting experiments must be excluded from the Mars-moon program,” he said. Asked later if such “experiments” included NASA’s approach to procuring human-rated lunar landers, which involve the agency ultimately buying landing services on commercially developed landers, Young agreed.

“A management experiment in my view would be to buy seats for crews to fly to the surface of the moon,” he said. “I personally think that these should be government-acquired assets under the leadership and direction of NASA.”

Young also stated that, with the addition of Artemis, NASA’s portfolio of human spaceflight programs may now be overloaded. “The plate is really full today,” he said. “I personally think that the leadership is going to have to, number one, prioritize, but number two is probably to eliminate some of the things that are currently being done that will interrupt having any opportunity of 2024, or I would say even 2028.”

One program that could be eliminated, at least for the initial return to the moon, is the lunar Gateway, he said later in the hearing. “I do not really see a required role for the Gateway in the lunar program,” he said, adding it could be useful in preparations for later missions to Mars. “There’s not a compelling argument to me for the Gateway for the lunar program.”

The hearing was not the first time some members of Congress, including Republicans, were critical of NASA’s approach to sending humans to the Moon. At the Oct. 16 appropriations hearing, Republican committee members pushed NASA to make greater use of the SLS over commercial launch vehicles. Agency officials said that wasn’t feasible given that the third SLS, needed for the Artemis-3 Orion mission that will send astronauts to the Gateway to meet up with a lunar lander that will take them to the surface, won’t be ready until 2024.

There was little disagreement among members and witnesses, though, about the importance of the long-term goal of sending humans to Mars. “The most compelling opportunity is humans to Mars,” Young said. “To have an objective of something like humans to Mars seems to be to be the inspiration and the beacon and the bright light. It’s way for our generation to tell the future generations there’s a lot of opportunity that’s out there, and don’t be turned off by just the fact that there are an awful lot of challenges because humans to Mars is just an incredible endeavor.”