NASA Administrator Jim Bridenstine testified before lawmakers Wednesday to make his case for a budget request to help the agency's plan to return humans to the moon in the next five years.
The House Appropriations subcommittee held the hearing on a plan by the Trump administration to accelerate the Artemis program by four years.
NASA's original budget request, which was based on the original moon-return goal of 2028, was submitted in March. After the goal was sped up to 2024, a new request was submitted for $1.6 billion.
"To a lot of members, the motivation just seems to be a political one, giving President Trump a moon landing in a possible second term, should he be reelected," Subcommittee Chairman Jose Serrano said.
Some lawmakers have been concerned that the moved-up date could cost an additional $25 billion over five years. So far, NASA has been unable to submit a final cost of the project.
"We want to give you those numbers," Bridenstine said. "We're not ready just yet, but certainly we still want to move forward."
While testifying Wednesday morning, Bridenstine said a return to the moon is necessary to keep pace with China and eventually send humans to Mars.
"We're less than a half of a percent of the federal budget," Bridenstine said. "You look at what we've been able to deliver, by creating technologies and capabilities that get commercialized, that elevate the human condition. I think the return on investment is just outstanding."
Republicans on the subcommittee agreed with Bridenstine's stance, but Democrats voiced concerns that the additional funding would take away from other government programs.
"I don't want to go to the moon by taking money from people who can't afford to survive in this society to the level that they should survive in this society," Serrrano said.
Congress remains in deliberation over NASA’s 2020 budget.