WASHINGTON — Launch vehicle company Relativity Space is growing its footprint at NASA’s Stennis Space Center in Mississippi by leasing an Apollo-era test stand to support development of its Terran R rocket.

The company announced Sept. 7 that it signed an agreement with Stennis to lease the A-2 test stand at the center. Relativity will pay $2.76 million to lease the test stand for seven years, with an option to extend the lease an additional 10 years.

The A-2 test stand was built in the 1960s for testing of the second stage of the Saturn 5 rocket, then used for Space Shuttle Main Engine tests through most of the shuttle program. It was mothballed nearly a decade ago after brief use testing the J-2X engine intended for the Ares rockets NASA had planned to develop for the Constellation program.

Relativity said it will refurbish the stand to support vertical testing of the reusable first stage of its Terran R rocket, increasing the engine thrust it can support from 650,000 to 3.3 million pounds-force. The company said the stand will enable a faster pace of testing of the stage.

“Exclusive access to these rare, national-asset facilities through partnership with NASA uniquely enables Relativity to develop a world-class launch vehicle,” Tim Ellis, chief executive of Relativity, said in a statement.

Relativity has been using other facilities at Stennis for several years, testing engines both for its original Terran 1 small launch vehicle and the larger Terran R. The company announced in October 2022 plans to build new test stands, office buildings and a vehicle hangar at Stennis. Relativity says it plans to invest $267 million overall on developing its facilities at Stennis, but did not disclose how much of that would go to the refurbishment of the A-2 test stand.

The A-2 test stand adds 30 acres to its footprint at Stennis, which now totals 298 acres. The company is the largest commercial tenant at the center.

“This increased footprint is a testament to Relativity’s continued progress in the commercial space arena,” said Rick Gilbrech, director of Stennis, in an agency statement. “It also is a testament to the value of NASA Stennis and our test complex infrastructure in supporting commercial space endeavors.”

Relativity announced in April it was retiring its Terran 1 rocket after a single launch in March that failed to reach orbit so it could focus on the Terran R, a medium- to heavy-lift vehicle with a reusable first stage. The Terran R is scheduled to make its first launch as soon as 2026.

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...