A ULA operated Atlas V 501 (RL10C-1) rocket was launched on its Flight AV-104 carrying a pair of KuiperSat spacecraft – dubbed KuiperSat-1 and KuiperSat-2. The launch took place from Cape Canaveral at 1806 GMT on 7 October 2023. The spacecraft are prototype satellites for Amazon’s Kuiper broadband communications satellite low Earth orbit constellation which is set to challenge SpaceX’s Starlink for dominations of space-based communications. The Centaur upper stage of the rocket, using its RL10C-1 engine, put the pair of satellites into a planned 504 x 483 km and 507 x 487 km orbits at 30 degrees inclination respectively. If the satellites prove successful, the first main batch of Kuiper constellation satellites willl be launched by a larger Atlas V 551 early next year.

Atlas V 501 launches KuiperSats-1 and -2 into orbit. Courtesy: Amazon