SpaceX launches mysterious RRT-1 mission, lands rocket on ship at sea (video)

A SpaceX Falcon 9 rocket launches the RRT-1 mission from Cape Canaveral Space Force Station in Florida on Dec. 16, 2024.

SpaceX launched the mysterious RRT-1 mission from Florida's Space Coast today (Dec. 16), after high winds scuttled a previous attempt.

A Falcon 9 rocket lifted off from Cape Canaveral Space Force Station today (Dec. 16) at 7:51 p.m. EDT (0051 on Dec. 17), kicking off a mission that SpaceX called RRT-1.

The company had aimed to launch RRT-1 on Friday (Dec. 13) but called off that attempt due to high winds.

A SpaceX Falcon 9 rocket launches the RRT-1 mission from Cape Canaveral Space Force Station in Florida on Dec. 16, 2024. (Image credit: SpaceX)

Many space observers think the RRT-1 mission is sending an advanced GPS satellite to orbit — specifically, GPS 3-10, another member of the venerable navigation network's third generation of spacecraft. SpaceX holds a contract to launch three of these satellites for the U.S. military and had already sent one of them aloft, in January 2023.

Related: SpaceX launches advanced GPS satellite for US Space Force, nails the landing

But SpaceX's RRT-1 mission description didn't say anything about GPS satellites; it didn't even explain what RRT-1 stands for, if that name is indeed an acronym. And the fairing that surrounded and protected the RRT-1 payload featured no artwork or logos, a departure from the norm that added to the intrigue.

In addition, SpaceX did not show any views of the Falcon 9's upper stage during today's webcast and ended the stream about 8.5 minutes after launch, at the request of the customer.

The first stage of a SpaceX Falcon 9 rocket rests on the deck of a drone ship shortly after launching the RRT-1 mission on Dec. 16, 2024. (Image credit: SpaceX)

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The Falcon 9's first stage came back to Earth about 8.5 minutes after launch tonight, touching down on the drone ship "A Shortfall of Gravitas" in the Atlantic Ocean as planned. It was the fourth liftoff and landing for this particular booster, according to SpaceX's mission description.

The rocket's upper stage, meanwhile, continued carrying the RRT-1 payload, whatever it may be, toward orbit. It will deploy the payload there about 90 minutes after launch, if all goes to plan.

Editor's note: This story was updated at 8:55 p.m. ET on Dec. 13 with news of the launch scrub, then again at 3:15 a.m. ET on Dec. 16 with news of the Dec. 16 target date. It was updated again at 8:10 p.m. ET on Dec. 16 with news of successful launch and rocket landing.