Hyperscaler Amazon has opted to use a different rocket company for the launch of its first Project Kuiper satellites.

The change, from ABL Space Systems’ RS1 rocket to United Launch Alliance (ULA)’s new Vulcan Centaur rocket, has led to the lift-off date for Amazon’s long-awaited Starlink competitor being pushed back until early next year. The launch of two prototype low-Earth orbit (LEO) satellites was originally scheduled to take place during Q4 2022.

Amazon didn’t offer an explanation for the late switch, and said it still plans to use RS1 for two launches at some point in the future. It is also still putting the finishing touches to those aforementioned prototypes – Kuipersat-1 and Kuipersat-2 – and expects them to be ready later this year.

“Our prototype mission will help us test how the different pieces of our satellite network work together, adding real-world data from space to results from our extensive lab testing, fieldwork, and simulation,” said Amazon, in a statement on Wednesday. “We’ll use findings from the mission to help finalise design, deployment, and operational plans for our commercial satellite system, which will provide reliable, affordable broadband to customers around the world.”

Indeed, when it eventually takes place, the launch will mark an important milestone on the road towards commercialisation. As well as giving Amazon an opportunity to field test its LEO satellites, it will also provide valuable experience with ULA, one of several launch partners tasked with putting Project Kuiper into orbit.

“We couldn’t be more excited to join the first launch of ULA’s Vulcan Centaur. We’ve already secured 38 Kuiper launches on Vulcan, and using the same launch vehicle for our prototype mission gives us a chance to practice payload integration, processing, and mission management procedures ahead of those full-scale commercial launches,” said Rajeev Badyal, VP of technology for Project Kuiper.

In April, Amazon announced it had scheduled 83 launches in total, but has since upped that figure to 92. These missions will carry into space the majority of the 3,236 satellites that will make up its constellation. In addition to ULA and ABL, Amazon is also working with France-based Arianespace, and Amazon founder Jeff Bezos’s Blue Origin.

Between Starlink, OneWeb, and myriad other budding satellite connectivity providers, low-Earth orbit looks set to be a pretty crowded bit of space by the time Project Kuiper enters commercial service.

Hopefully the addressable market for LEO coverage is large and diverse enough to support all of these competing constellations, and that the new breed of satellite operators hoping to take on Amazon and Space-X are on sound financial footing. Because if not, it could lead to a lot of moribund satellites cluttering up the skies.

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