The coronavirus pandemic on Earth is knocking NASA’s moon plans off course.

On Thursday evening, Jim Bridenstine, the space agency’s administrator, announced the suspension of the manufacture and testing of the Space Launch System and Orion, the giant rocket and crew capsule that would be used to take astronauts back to the moon.

The Trump administration had set a goal of the next moon landing occurring by the end of 2024. With the spread of the coronavirus, however, NASA is now shutting down work at the Michoud Assembly Facility in New Orleans, where the rocket is being built, and the Stennis Space Center in Mississippi, about 45 miles to the northeast of Michoud. The first Space Launch System booster is being tested at Stennis.

There has been one confirmed case of the coronavirus among Stennis employees. There are no confirmed cases at Michoud, but the number of infected people in the New Orleans area has risen quickly in the past few days.

The directive from Mr. Bridenstine is for workers at the two NASA sites to work remotely, but there is no way to build or test a rocket without people at the sites. The change takes effect on Friday.