When the first two segments of NASA’s Gateway station make their way to the Moon sometime in 2024, they’ll be carried into space by a Falcon Heavy rocket. The $331.8 million agreement, which the agency announced on Tuesday, is the second launch contract NASA has awarded to SpaceX in as many weeks.

Once it’s safely in lunar orbit, the Gateway will serve as a way station for astronauts and equipment heading to the Moon as part of NASA’s Artemis program. The pair of modules SpaceX will ferry into space are the power and propulsion element (PPE) and the habitation and logistics outpost (HALO), which two separate companies are building for NASA for $375 million and $187 million respectively. The former will provide Gateway with power and allow the station to move to different lunar orbits, while the latter will give astronauts a place to stay on their way to the Moon. The mission will blast off from Kennedy Space Center in May of 2024 at the earliest. 

In the lead up to Artemis, NASA has been awarding contracts to private companies to speed up the project’s timeline. In January, however, it came out that the agency had quietly pushed back the award timeframe for two lander contracts from late February to the end of April, which has cast doubt over whether NASA will be able to meet its ambitious 2024 goal for Artemis.