“NASA has a history of not meeting launch dates,” said Jim Bridenstine, NASA’s administrator, at a Senate committee hearing Wednesday, “and I’m trying to change that.”

NASA plans to send its Orion capsule, designed to carry astronauts on deep space missions, on a crewless test trip around the moon next year.

But the schedule for completing the rocket that is to carry Orion — known as the Space Launch System — has slipped repeatedly despite NASA’s spending more than $10 billion on the program. Last year, in announcing the latest delay, NASA said that the mission was penciled in for the end of 2019 but even then conceded that June 2020 was a more realistic target date.

In October, NASA’s inspector general issued a report that was sharply critical of Boeing, the rocket’s prime contractor. “Cost increases and schedule delays of core stage development can be traced largely to management, technical, and infrastructure issues driven by Boeing’s poor performance,” the report said.

On Wednesday, Bridenstine said that last week it had become clear that the rocket would probably not be ready even by June 2020. He said he had directed managers to explore whether there would be another way to launch.

“The goal is to get back on track,” Bridenstine said. He said the space agency would make a decision “in the next couple of weeks,” and that it might require additional money from Congress.

The largest rockets currently built by private companies are smaller than the Space Launch System, so if NASA decides on this approach, the payload for the mission would need to be split between two rockets. The Orion capsule and its service module, a component built by the European Space Agency to provide power and propulsion, would ride to orbit on one rocket. A fueled rocket stage for propelling Orion to the moon would go up separately.

A commercially launched mission would allow extended testing of Orion and the service module, one of the main goals, but it would push the first flight of the Space Launch System further into the future.

This article originally appeared in The New York Times.