NASA missed another opportunity today to reveal how much the Trump Administration’s proposal to return astronauts to the lunar surface by 2024 will cost. At a House Science, Space, and Technology subcommittee hearing, NASA witnesses said the agency has provided preliminary estimates to the White House Office of Management and Budget (OMB), but OMB has not cleared them yet. Until it does, it cannot share any information with Congress or the public.

Rep. Kendra Horn (D-Oklahoma), who chairs the Space and Aeronautics Subcommittee, said “we’re flying blind” with a White House directive to land people on the Moon just 5 years from now but “no plan or no budget details.”

Whenever those details are made public, that does not mean Congress will agree. Full committee chairwoman Rep. Eddie Bernice Johnson (D-Texas) expressed support for a “strong, forward-leaning human and robotic exploration program,” but not at the price of science programs at NASA or other agencies. Noting that the Trump FY2020 budget request proposes billion dollar cuts to the National Science Foundation (NSF) and NOAA, and a 30 percent cut to the National Institute of Standards and Technology (NIST), she warned that any attempt to increase NASA’s budget to accelerate the human lunar landing program would be weighed against the “opportunity cost of doing so.”

On March 26, Vice President Pence directed that NASA land “the next man and the first woman” at the South Pole of the Moon by 2024, 4 years earlier than NASA was planning. NASA Administrator Jim Bridenstine has stated several times that it was a presidential decision announced by the Vice President, but Johnson noted that in the intervening six weeks, “the President has been uncharacteristically silent” about it, “making no public statements or tweets in support of his lunar initiative.”

Bridenstine testified to the full House SS&T committee on April 2 and said he hoped to get a revised FY2020 budget request to Congress by April 15, but that date came and went with no news.

Today, Horn asked when Congress would get it and why it is taking so long. Bill Gerstenmaier, the head of NASA’s human spaceflight program, replied:

“We need a really solid plan… We’re busy establishing those plans, we also have to go through the Administration and get budget approval, make sure we understand where we are, even look at the out-years… We’re taking the time to get that right. We’re probably several weeks away, maybe a week to two weeks away from being able to give you a plan.” Bill Gerstenmaier

Getting it right, whether the plan or the budget proposal, was a major theme of the hearing, both from the NASA witnesses and committee members. Rep. Frank Lucas (R-Oklahoma), Ranking Member of the full committee, stressed that whatever the request is, it must be realistic. Recounting the failures of the last two attempts to resume human landings on the Moon — President George H.W. Bush’s 1989 Space Exploration Initiative and President George W. Bush’s Constellation program — he urged the Administration “to provide a realistic funding proposal” that Congress can approve.

Subcommittee Ranking Member Brian Babin (R-Texas) said much the same thing. “We need to be cautious about developing a plan that is overly ambitious or costly, and we need to ensure that OMB sufficiently funds the plan in subsequent budget requests.”

Members seemed generally positive about the idea of accelerating a human return to the Moon, but with caveats about not only the cost, but ensuring safety is not sacrificed to meet schedule. As Babin said, balance is needed between “setting challenging yet achievable goals and taking prudent steps to ensure safe operations…”

Patricia Sanders, chair of NASA’s Aerospace Safety Advisory Panel (ASAP), addressed the question of “how safe is safe enough” by cautioning that the meaning of “safe” in the context of a complex, technical space program is not the same as in day-to-day life. “The risk tolerance decision requires balancing many factors such as financial cost, schedule, national prestige, international relationships, human welfare, public opinion, and ethical considerations, to determine if the chance of a mishap is outweighed by the likely mission benefit.”

Still, she reiterated concerns expressed at the last ASAP meeting that unrealistic schedules can result in poor decisions from a safety perspective.

The topic of the hearing was “Keeping Our Sights on Mars,” which was the goal of the Obama Administration’s human exploration program — putting humans into orbit around Mars in the 2030s with landing to come sometime thereafter. Some members of this committee, especially Rep. Ed Perlmutter (D-Colorado), are passionate advocates for accelerating THAT goal, specifically a human landing in 2033. The Earth and Mars align properly in their orbits every 26 months to allow direct flights between the two planets. Some of these windows are more advantageous than others and 2033 is one of the best. He waves Mars 2033 bumper stickers at almost every NASA-related hearing and today was no exception.

A recent study by the Science and Technology Policy Institute (STPI) concluded that 2033 is “infeasible,” but Perlmutter is not dissuaded. He asked Cornell University’s Jonathan Lunine, co-chair of the 2014 “Pathways” study by the National Academies of Sciences, Engineering, and Medicine, if “infinite resources” would allow the goal to be met. Lunine said his report estimated that one could get to Mars in the mid-2030s, but that was 5 years ago. So 5 more years would have to be added to that now.

That would make it the late 2030s at best, which agrees with STPI’s conclusion. It estimated 2035 or 2037 under certain budget scenarios, but 2039 is more realistic.