United Launch Alliance Successfully Launches Amazon Leo Satellites on Atlas V

United Launch Alliance (ULA) confirmed the successful launch of its Atlas V 551 rocket on Monday, December 15, 2025, carrying a new batch of production satellites for Amazon Leo, the entity formerly known as Project Kuiper.

The critical mission lifted off from Space Launch Complex 41 (SLC-41) at Cape Canaveral Space Force Station, Florida, in the early morning hours. This launch successfully placed 27 additional spacecraft into their designated Low Earth Orbit (LEO) configuration. This deployment brings the total operational count for the Amazon Leo constellation to 180 units, excluding the two prototype satellites launched in October 2023. The mission officially carried the Amazon Leo designation following the program's rebranding on November 13, 2025, signaling a transition toward full operational status.

The Atlas V 551 variant utilized for this deployment is the most powerful in the Atlas V family, characterized by five strap-on solid rocket boosters and a medium payload fairing. The rocket stands approximately 197 feet tall and generates about 2.6 million pounds of thrust at liftoff, primarily from its RD-180 main engine and the solid boosters.

This successful flight is a key component of a substantial commercial agreement where ULA is contracted to launch the majority of Amazon Leo's planned constellation, which is intended to eventually exceed 3,200 satellites to establish global broadband internet coverage. ULA's overall agreement with Amazon Leo encompasses eight Atlas V launches and 38 launches utilizing the newer Vulcan rocket.

Amazon Leo, managed by Kuiper Systems LLC, is targeting low round-trip latency between 30 and 50 milliseconds, significantly faster than conventional geostationary systems. The constellation is designed to operate across three orbital layers at altitudes ranging from 590 km to 630 km, spread across 98 orbital planes. Continued launches are essential for Amazon Leo to meet the Federal Communications Commission (FCC) requirement to have at least 50% of the full constellation operational by July 30, 2026.

The satellites incorporate advanced technology, including Optical Inter-Satellite Links, which create a robust mesh network in space for high-speed data transfer between the spacecraft. This deployment effort positions Amazon Leo to compete with established networks like Starlink, which has already deployed over 9,000 satellites in LEO as of this launch date.

The Atlas V rocket, which has a history of supporting significant missions such as New Horizons and Juno, uses a Russian-made RD-180 engine for its first stage and a Centaur upper stage. This launch reinforces ULA's standing as an experienced launch provider, a joint venture between Lockheed Martin Space Systems and Boeing Defense, Space & Security since December 2006.