LA-based Relativity Space announced a deal with Telesat today to launch a portion of its new internet satellite constellation.

The news: Canadian communications company Telesat has committed to sending some of its low Earth orbit (LEO) satellites up on Relativity’s Terran 1 rocket. The deal is the first large launch contract for the startup, which plans to manufacture its satellites with 3D printing. “It’s really a big vote of confidence in our team and our technology,” says CEO Tim Ellis.

The details: Relativity joins Jeff Bezos’s Blue Origin, Telesat’s other committed launch provider. While the number of launches and satellites each company will perform is still under wraps, you can bet there will be a lot to go around. LEO constellations typically require hundreds of small satellites to get reliable worldwide coverage. Take satellite internet company OneWeb, which launched the first members of its 650-satellite constellation earlier this year.

But first … Relativity hasn’t even completed a space-ready rocket yet. The company has been doing a number of engine tests and construction on additive-manufacturing facilities, but it has yet to launch one. It says it is on track to test-launch its first 3D-printed Terran 1 rocket in 2020 and recently acquired the space in Cape Canaveral, Florida, to do so. If initial tests go to plan, the startup is looking at its first commercial launch in 2021.

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