T-Cellular’s protection will get an enormous enhance from SpaceX’s Starlink satellites, beginning with texts

T-Mobile subscribers will be getting a satellite upgrade to their wireless service, thanks to a newly announced partnership that takes advantage of SpaceX’s Starlink constellation.

But don’t expect to start streaming high-definition videos via satellite to your T-Mobile connected devices immediately: The beta version of Starlink’s broadband boost won’t start rolling out in select areas until next year, after a series of SpaceX satellite launches.

That rollout will begin with text messaging, including SMS, MMS and messaging apps. Voice and data coverage will come later.

T-Mobile CEO Mike Sievert and SpaceX CEO Elon Musk laid out the details behind the deal today during a live presentation at SpaceX’s Starbase facility in South Texas.

Sievert said the partnership calls for creating a new network, composed of Starlink satellites that can use T-Mobile’s mid-band spectrum nationwide. He said the vast majority of smartphones already on its network would be compatible with the new satellite-plus-cellular service.

“You can connect with your existing phone,” Sievert promised. He said he expected to include the Starlink-enabled service free with T-Mobile’s most popular plans. With less popular plans, a monthly fee might be charged, he said.

The hybrid service is designed to be available practically anywhere in the continental U.S. and Hawaii, plus parts of Alaska, Puerto Rico, U.S. territorial waters and vast stretches of the world’s oceans. That means T-Mobile’s customers could get a signal in traditionally inaccessible locales, including national parks and wilderness areas.

Sievert called it “the end of mobile dead zones.”

Musk played up the idea that people who get into trouble in isolated areas would be able to get in contact with the outside world, even if no cell towers were available. “It will save lives,” he told the crowd.

SpaceX is already the world’s leader in providing satellite broadband service from low Earth orbit. Over the past three years, it has launched more than 3,000 of its Starlink satellites, which are manufactured at SpaceX’s facility in Redmond, Wash. About 2,300 of those satellites are currently in operation, according to satellite-watcher Jonathan McDowell’s Starlink Statistics webpage.

Musk said the new generation of satellites would have to be equipped with large, “extremely advanced” antennas. “It’s a hard problem, that why it’s not been solved before,” he said.

The next-generation satellites will be designed for launch on SpaceX’s giant Starship rocket, which is currently under development. If that development effort runs into snags, SpaceX may come up with an interim solution that would allow the satellites to be launched on the workhorse Falcon 9 rocket, Musk said.

Starlink is said to have more than 400,000 subscribers worldwide, while Bellevue, Wash.-based T-Mobile US reports having 110 million customers. The newly announced team-up could boost T-Mobile in its competition with the likes of Verizon and AT&T for cellular customers, and strengthen SpaceX’s hand as Starlink goes up against OneWeb and Amazon’s yet-to-be-launched Project Kuiper satellite broadband network.

Financial details behind the partnership were not immediately announced.

Looking ahead, Sievert didn’t rule out the idea that T-Mobile could have Starlink handle backhaul transport for its data. “Well, we’re open to that, and we’re partners now,” he said.

Although T-Mobile and SpaceX made clear that the new service would be phased in gradually, starting next year, they laid out a grand vision for what T-Mobile called “Coverage Above and Beyond.” Sievert invited telecom network providers around the world to collaborate on global connectivity, with T-Mobile committing itself to offering reciprocal roaming to those providers who accept the invitation.

Musk went even further when he was asked how the partnership with T-Mobile meshed with his plans for solar system exploration and settlement.

“We’d love to have T-Mobile on Mars,” Musk said, sparking cheers from the crowd.

Update for 6:45 p.m. PT Aug. 25: In a tweet, Musk emphasized that the T-Mobile-Starlink system as currently envisioned may not be capable of, say, streaming that high-definition movie:

Watch the full presentation on YouTube