WASHINGTON — The chairman of the House appropriations subcommittee that funds NASA said July 24 he’s not yet convinced of the need to accelerate a human return to the moon, citing the cost of doing so.

At a hearing of the commerce, justice and science (CJS) subcommittee of the House Appropriations Committee about the Office of Science and Technology Policy, Rep. José Serrano (D-N.Y.) said that while he and other committee members supported NASA in general, he didn’t understand why it was so important to move up the schedule for landing humans on the moon to 2024.

“While I support a continued human presence in space, I remain concerned about the estimated cost — in excess of $20 billion over the next few years — to unnecessarily speed up by just four years the schedule for returning American astronauts to the moon,” he said in his opening remarks. “Arbitrarily changing this schedule will have grave consequences for other vital programs across the science fields and other programs across the government.”

Serrano then departed from his prepared opening statement to emphasize this point. “Mr. Aderholt and I are big supporters of NASA,” he said, referring to the subcommittee’s ranking member, Rep. Robert Aderholt (R-Ala.) “I just disagree with spending this money on moving something up a couple of years. It’s not that we oppose going to the moon.”

Serrano returned to the subject later in the hearing in a series of questions to the sole witness, Kelvin Droegemeier, director of OSTP. “Is it even technically possible, financially responsible or necessary to launch a manned moon mission four years early at an additional $20 billion cost simply to meet a political deadline?” Serrano asked.

Droegemeier acknowledged that the $1.6 billion in additional funding that the administration sought in a fiscal year 2020 budget amendment released in May is a “down payment” on the total cost of the Artemis program through a 2024 landing. However, he said he estimated the total additional cost would be less than $20 billion.

“You don’t know how much less?” Serrano asked him of the cost estimate.

“I don’t know how much less, but I heard it was less than $20 billion,” Droegemeier responded. NASA Administrator Jim Bridenstine, who gave a cost estimate of $20–30 billion in an interview in June, has more recently suggested it could cost “well under” $20 billion. However, he told senators at a Senate Commerce Committee hearing July 17 that a full cost estimate likely would not be available until the agency’s fiscal year 2021 budget proposal is released in early 2020.

Serrano appeared unconvinced by arguments for accelerating a human return to the moon to 2024, versus the agency’s earlier plans for a 2028 landing. “What can we gain, other than the ability to claim we were there first this time around?” he asked.

“I think it’s more than a political thing,” Droegemeier responded. “It ties in with the mission of going to Mars, it ties in with timelines of what private companies are doing.”

However, he deferred specifics about the Artemis program, or the reasons why returning humans to the moon by 2024 was important, to Bridenstine. “It’s a pretty complicated, sort of complicated, ecosystem, and I think Jim is much better suited to addressing that than I am,” he said.

“We are serious in continuing to be helpful to NASA and to space exploration, but that this is a big ask at a difficult time,” Serrano responded, adding that “you’ll see how difficult it’s going to get in the next few days around here about dollars and cents.”

That last comment appeared to refer to the two-year budget deal announced by the White House and Congressional leadership July 22, which would lift spending caps and avoid automatic budget cuts. The deal would increase non-defense discretionary spending, which includes NASA, but by somewhat less than what the Democratic leadership in the House initially sought.

The House passed in June a CJS spending bill, part of a “minibus” of several appropriations bills. That bill did not include the $1.6 billion in additional spending for Artemis, in part because the budget amendment was submitted days before Serrano’s subcommittee marked up the bill. That bill will have to be reconciled with a Senate version yet to be introduced while fitting into the revised overall spending caps, an effort that will involve Serrano and other appropriators.

In recent days, Bridenstine has visited with several House appropriators. He tweeted out July 16 and 17 pictures of him meeting with Serrano as well as Reps. Marcy Kaptur (D-Ohio) and Charlie Crist (D-Fla.), who also serve on the CJS appropriations subcommittee.

Bridenstine in one tweet thanked Serrano for his “continued support” of NASA’s programs. “We both agree that ongoing bipartisan support in Congress is critical for NASA’s return to the Moon and on to Mars as we inspire the #Artemis generation,” he wrote.