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Additional Media

Watch live: ULA Atlas 5 rocket launches 27 Amazon Leo satellites from Cape Canaveral

Watch live coverage of the launch of a United Launch Alliance Atlas 5 rocket with the third batch of 27 satellites for Amazon's Leo internet service on Tuesday, Dec. 16, 2025. Liftoff is scheduled during a 29-minute launch window that opens at 3:28 a.m. EST (0828 UTC). Amazon’s LEO satellite …

ULA Atlas V 551 launches Amazon Leo Atlas 4 (LA-04)

ULA Atlas V launch of the Amazon Leo Atlas 4 (LA-04) mission from SLC-41. Launch Window: December 16th from 3:28AM to 3:57AM EST (08:28-08:57 UTC) Current T0: December 16th at 3:49AM EST (08:28 UTC) Mission: Atlas V 551 launch of a batch of 27 Amazon Leo satellites Launch location: Space …

Atlas V Amazon Leo 4

ULA's Atlas V rocket will deliver another batch of satellites into low Earth orbit for Amazon Leo, the broadband constellation. Its mission is to provide fast, reliable internet to customers around the world, including those in unserved and underserved communities, using a network of more than 3,000...

Amazon Leo (LA-04)

Overview

Destination: Low Earth Orbit
Mission: Communications

Low Earth Orbit Space Launch Complex 41 Cape Canaveral SFS, FL, USA Probability: 90%

Amazon Leo, formerly known as Project Kuiper, is a mega constellation of satellites in Low Earth Orbit that will offer broadband internet access, this constellation will be managed by Kuiper Systems LLC, a subsidiary of Amazon. This constellation is planned to be composed of 3,276 satellites. The satellites are projected to be placed in 98 orbital planes in three orbital layers, one at 590 km, 610 km and 630 km altitude.

Telemetry

Launch trajectory and telemetry simulations provided by Flight Club - a rocket launch simulator and orbital trajectory visualiser for all things space!

Updates

Cosmic_Penguin • Dec. 16, 2025, 10:03 a.m.

Launch success.


Nosu • Dec. 16, 2025, 8:28 a.m.

Liftoff


LL2 • Dec. 16, 2025, 8:07 a.m.

Official Webcast by United Launch Alliance has started


Cosmic_Penguin • Dec. 16, 2025, 6:38 a.m.

Updated launch weather.


Cosmic_Penguin • Dec. 14, 2025, 6:43 p.m.

Delayed to December 16 due to launch site ground winds.


Atlas V 551

Family:
Configuration: 551

Atlas V is an expendable launch system in the Atlas rocket family. It was formerly operated by Lockheed Martin and is now operated by United Launch Alliance (ULA), a joint venture with Boeing. Each Atlas V rocket uses a Russian-built RD-180 engine burning kerosene and liquid oxygen to power its first stage and an American-built RL10 engine burning liquid hydrogen and liquid oxygen to power its Centaur upper stage. The RD-180 engines are provided by RD Amross, while Aerojet Rocketdyne provides both the RL10 engines and the strap-on boosters used in some configurations. The standard payload fairing sizes are 4 or 5 meters in diameter and of various lengths. Fairings sizes as large as 7.2 m in diameter and up to 32.3 m in length have been considered. The rocket is assembled in Decatur, Alabama and Harlingen, Texas.

Specifications
  • Minimum Stage
    1
  • Max Stage
    2
  • Length
    59.7 m
  • Diameter
    3.8 m
  • Fairing Diameter
    5.4 m
  • Launch Mass
    573.0 T
  • Thrust
    12269.0 kN
Family
  • Name
    Atlas V 551
  • Family
  • Variant
    551
  • Alias
  • Full Name
    Atlas V 551
Payload Capacity
  • Launch Cost
    $153000000
  • Low Earth Orbit
    18850.0 kg
  • Geostationary Transfer Orbit
    8890.0 kg
  • Direct Geostationary
    3850.0 kg
  • Sun-Synchronous Capacity

United Launch Alliance

United Launch Alliance

(ULA)

Interim CEO: John Elbon Founded: 2006 Successes: 171 Failures: 0 Pending: 40

Agency Type:

United Launch Alliance (ULA) is a joint venture of Lockheed Martin Space Systems and Boeing Defense, Space & Security. ULA was formed in December 2006 by combining the teams at these companies which provide spacecraft launch services to the government of the United States. ULA launches from both coasts of the US. They launch their Atlas V vehicle from LC-41 in Cape Canaveral and LC-3E at Vandeberg. Their Delta IV launches from LC-37 at Cape Canaveral and LC-6 at Vandenberg.

INFO WIKI

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Cape Canaveral SFS, FL, USA

Space Launch Complex 41


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