The scheduled Sunday launch could mark a new phase in competition in the commercial space market, and pave the way for the deployment of Amazon's Kuiper satellite network.

The business battle between the two wealthiest people in the world moves to Spain. Amazon Kuiper, the tech giant's division to provide high-speed and affordable internet via low-orbit satellites, has obtained government authorization to operate.

Doing that on a maiden flight would be unprecedented: that kind of partial reusability was pioneered by SpaceX, Elon Musk’s rocket firm, and it required several attempts before eventually sticking the landing in 2016.