The fourth launch of the United Launch Alliance (ULA) Atlas V 551 rocket carrying the next batch of production satellites for Amazon Leo (formerly Project Kuiper), Leo 4, is planned for Dec. 15, 2025, pending range approval. The launch window opens at 3:52 a.m. EST. This launch continues a new chapter in the commercial launch industry as Amazon Leo partners with ULA to deliver the majority of its advanced satellites to low Earth orbit (LEO).
Atlas V to launch Amazon Leo 4ULA'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 3,200 LEO satellites.Launch Date and Time: Monday, Dec. 15, 2025 with a window opening at 3:52 a.m. ESTGO Atlas! GO Centaur! GO Amazon Leo!
1941-EX-ST-2025 [Nov 17]QuoteLaunch vehicle communications for the launch of Atlas V vehicles with commercial satellites from Space Launch Complex 41 (LC-41) at Cape Canaveral Space Force Station.Operation Start Date: 12/13/2025Operation End Date: 03/13/2026I assume this is for a Kuiper Amazon LEO launch (KA-04), seeing as only one commercial Atlas V launch customer remains on the manifest.
Launch vehicle communications for the launch of Atlas V vehicles with commercial satellites from Space Launch Complex 41 (LC-41) at Cape Canaveral Space Force Station.Operation Start Date: 12/13/2025Operation End Date: 03/13/2026
Our next mission with @ulalaunch — and our first as Amazon Leo — is set for NET Mon. Dec. 15, with the launch window opening at 3:52 a.m. EST. Fast facts on LA-04 (Leo Atlas 4):➡️ Amazon’s fourth Atlas V launch➡️ Seventh mission of the year➡️ Adds 27 satellites to our constellation
Upcoming missionsLA-04: Amazon Leo’s next mission set for Monday, Dec. 15United Launch Alliance (ULA) is targeting Monday, Dec. 15 for our Leo Atlas 4 (LA-04) mission. Named LA-04 for Amazon’s fourth launch on an Atlas V rocket, the mission will send another 27 satellites to low Earth orbit, bringing the total number of Amazon Leo spacecraft launched to date to 180 satellites. The mission will launch from Space Launch Complex 41 at Cape Canaveral Space Force Station in Florida, with the launch window opening at 3:52 a.m. EST. The mission marks Amazon Leo’s fourth launch on Atlas V and the first as Amazon Leo.Mission No. 7Mission name: LA-04 (Leo Atlas 4)Launch vehicle: ULA Atlas V 551Launch date/time: The window opens on Monday, December 15, 2025, 3:52 a.m. EST.Number of satellites: 27Launch site: Space Launch Complex-41, Cape Canaveral Space Force Station
United Launch Alliance (ULA) hoists its Atlas V booster into the Vertical Integration Facility (VIF) adjacent to Space Launch Complex-41 at Cape Canaveral Space Force Station. The rocket will launch the Leo Atlas 4 (LA-4) mission for Amazon's broadband satellite constellation.
Will all the previous launch threads be retroactively renamed to LA/LV-X?
Launch processing efforts are underway to prepare our fourth Atlas V mission to deliver 27 advanced broadband satellites into space for the Amazon Leo constellation. The Amazon Leo 4 mission is targeting launch in the early morning hours of Dec. 15 from Cape Canaveral, Florida. Spectators from Florida to the Carolinas, New York City, New England and beyond will get a chance to see the rocket streaking into space, weather permitting in your area. Follow mission progress: http://bit.ly/av_leo4 Photos: https://flic.kr/s/aHBqjCBBpT
Launch Date and Time: Monday, Dec. 15, 2025 with a window opening at 3:35 a.m. EST
ULA technicians today transported the Amazon Leo Atlas 4 (LA-4) payload to the Vertical Integration Facility and hoisted the encapsulated satellites atop the Atlas V. This high-performance rocket, nicknamed "The Bruiser," will launch the satellites into space Dec. 15 to enhance broadband access and help connect the world. Launch info: http://bit.ly/av_leo4
Domi207 — 5:26 AMAn Atlas V fairing with 27 Kuiper satellites inside for the LA-04 mission has rolled out to SLC-41. The launch is currently scheduled to happen in 9 days
Launch Date and Window: Monday, Dec. 15, between 3:49 and 4:18 a.m. EST (0849-0918 UTC)
Amazon Leo@AmazonleoLA-04 update: Our encapsulated payload left Amazon’s processing facility on Friday for integration with Atlas V, with @ulalaunch targeting Dec. 15 to send another 27 Leo satellites into orbit.
ULA@ulalaunchAtlas V then reaches Mach 1 as it climbs through the atmosphere. About 96 seconds into ascent the solid rocket boosters complete their burn and separate.
ULA@ulalaunchWith the boosters jettisoned, the guidance system steers Atlas V toward its precise target in space. The 5-meter payload fairing continues to protect the Leo satellites during this phase of flight.
QuoteULA@ulalaunchOnce the rocket crosses the Karman line and enters space, the payload fairing is jettisoned. The first stage then completes its burn and separates from the vehicle.
ULA@ulalaunchOnce the rocket crosses the Karman line and enters space, the payload fairing is jettisoned. The first stage then completes its burn and separates from the vehicle.
ULA@ulalaunchCentaur begins second stage flight at less than seven percent of the rocket’s liftoff mass. Its RL10 engine ignites to place the mission into a circular low Earth orbit.
ULA@ulalaunchAfter engine shutdown, Centaur rotates to the correct orientation and releases @Amazonleo satellites, continuing their mission to provide reliable internet coverage around the world.
ULA@ulalaunchWatch live December 15Broadcast: 3:28 A.M EST
Primary Launch Day 15 DEC 0835Z-1026Z Backup Launch Day 16 DEC 0813Z-1004Z Backup Launch Day 17 DEC 0752Z-0943Z Backup Launch Day 18 DEC 0731Z-0922Z Backup Launch Day 19 DEC 0709Z-0900Z Backup Launch Day 20 DEC 0648Z-0839Z Backup Launch Day 21 DEC 0627Z-0818Z
Airspace EvaluationThe National Airspace System (NAS) hazard area evaluation examined five Aircraft Hazard Areas (AHAs) and the Special Use Airspace (SUA) associated with this launch. The first, AHA-A, extends from the launch site to 88nm northeastward. The second, AHA-B, extends from 108nm northeast of the launch site to 191nm northeast. The third, AHA-C, extends from 441nm northeast of the launch site to 641nm northeast.These three AHAs are within Miami, Jacksonville and New York ARTCCs. The forth, AHA-D, extends from 1789nm northeast of the launch site to 2100nm northeast and is located in the Gander FIR. A fifth AHA safeguarding the Stage 2 reentry is located west of Central America in the Mazatlan, Tahiti and Oakland FIRs.
Realistically, this is the last ULA launch of 2025?
Quote from: zubenelgenubi on 12/09/2025 11:20 pmRealistically, this is the last ULA launch of 2025?The shortest pad turnaround I found for SLC-41 since ULA acquired it in 2006 is 29 days, so yes.
Quote from: DanClemmensen on 12/09/2025 11:39 pmQuote from: zubenelgenubi on 12/09/2025 11:20 pmRealistically, this is the last ULA launch of 2025?The shortest pad turnaround I found for SLC-41 since ULA acquired it in 2006 is 29 days, so yes.I had a tiny bit of hope that they would be able to pull off a dual stack and back-to-back launch with Vulcan this year, but that's out of the question now. Bruno has all but confirmed a NET January on KV-01. I'm still holding out hope for a Vulcan stack to commence this month, though. Maybe even two...
Quote from: sstli2 on 12/10/2025 12:16 amQuote from: DanClemmensen on 12/09/2025 11:39 pmQuote from: zubenelgenubi on 12/09/2025 11:20 pmRealistically, this is the last ULA launch of 2025?The shortest pad turnaround I found for SLC-41 since ULA acquired it in 2006 is 29 days, so yes.I had a tiny bit of hope that they would be able to pull off a dual stack and back-to-back launch with Vulcan this year, but that's out of the question now. Bruno has all but confirmed a NET January on KV-01. I'm still holding out hope for a Vulcan stack to commence this month, though. Maybe even two...In an earlier discussion, someone pointed out that they cannot begin the next stack until after the current one actually launches, because the VIF must remain available in case the current one needs to roll back. I have never been anywhere near that VIF, so I cannot confirm this, but it sounds reasonable. A parallel stacking process will need VIF-A to come on line.
Issue Date UTC: 12/09/2025 0012Start Date UTC: 12/15/2025 0948End Date UTC: 12/21/2025 0956B2767/25 NOTAMNQ) MMFR/QRDCA/IV/BO/W/000/999/A) MMFOB) 2512150948C) 2512210956D) 15 0948-1204, 16 0926-1142, 17 0905-1121, 18 0844-1100, 19 0822-1038, 20 0801-1017, 21 0740-0956E) DANGEROUS AREA FOR REENTRY OF ROCKET ULA KA-04 STAGE 2: LATERAL LIMIT AREA FORMED BY THE UNION OF THE FLW POINTS: 1006N12000W - 0856N11825W - 0645N12000W - 1006N12000W FIR OCEANICO MAZATLAN (MMFO)F) SFCG) UNL
The Launch Readiness Review is GO to continue preps for launch of Atlas V with our fourth Amazon Leo constellation mission. Liftoff is planned for Monday at 3:49 a.m. EST (0849 UTC) from Cape Canaveral. Early weather forecast is 65% favorable. Live updates and webcast: http://bit.ly/av_leo4
Launch Readiness Review completedThe Launch Readiness Review (LRR) is GO for Monday's predawn liftoff of the United Launch Alliance Atlas V rocket with another batch of production satellites for the Amazon Leo constellation.Liftoff is scheduled for 3:49 a.m. EST (0849 UTC) from Space Launch Complex-41 at Cape Canaveral Space Force Station in Florida.The LRR, led by ULA Launch Director Don Malin, was completed this morning at the Advanced Spaceflight Operations Center (ASOC).Leadership from ULA, Amazon and Space Force assessed the readiness of the rocket, payload and mission assets, discussed the status of pre-flight processing work, heard technical overviews of the countdown and flight, and previewed the weather forecast that projects 65 percent chance of meeting the launch rules.At the conclusion of the meeting, senior leaders were polled and gave a ready status for launch, then signed the Launch Readiness Certificate.The Atlas V rocket, designated AV-111, stands 205 feet (62.5 meters) tall and will launch the Leo 4 payload into near-circular low Earth orbit (LEO) of approximately 280 miles (450 km) and 51.9 degrees inclination. At liftoff, the rocket generates a combined thrust of 2.7 million pounds (12 megaNewtons) from its main engine and five solid rocket boosters. ULA will offer live reports from launch control in our automatically refreshing blog beginning Monday at 12:30 a.m. EST (0530 UTC). The launch webcast starts 20 minutes before liftoff.
ULA@ulalaunch·Attention rocket fans in the eastern U.S.! Here is your chance to see Atlas V streaking into orbit Monday morning carrying the next mission for the Amazon Leo broadband satellite constellation. This visibility map shows when and where your best chances are to see the rocket as it lifts off at 3:49 a.m. EST (0849 UTC) and heads northeasterly into space.ULA will offer live reports from launch control in our automatically refreshing blog beginning at 12:30 a.m. EST (0530 UTC). The launch webcast starts at L-20 minutes. http://bit.ly/av_leo4
Elisar Priel@ENNEPS·@ulalaunch is getting ready for the next launch of its Atlas V 551 rocket from SLC 41 at the CCSFS, as the rocket rolled out from the Vertical Integration Facility and towards the pad ahead of Sunday Night's Amazon Leo LA-4 mission.
ULA@ulalaunch·United Launch Alliance announces the arrival of our Atlas V rocket at its Cape Canaveral pad to launch Amazon Leo 4 on Monday at 3:49 a.m. EST (0849 UTC). This will be ULA's fourth of 46 missions dedicated to delivering @Amazonleo satellites into low Earth orbit for the broadband constellation to connect the world. http://bit.ly/av_leo4
Rollout is underway of the United Launch Alliance Atlas V rocket to send the next batch of Amazon Leo broadband satellites into space Monday. Liftoff of the Leo 4 mission is planned for 3:49 a.m. EST (0849 UTC).
The MLP has been lowered onto the launch pad piers, accomplishing the "harddown" milestone at 11:51 a.m. EST. Over the next few hours today, umbilical connections will be made with launch pad systems, the environmental control system feeding conditioned air to the rocket and payload will be switched to facility supplies to allow the portable trailers used during rollout to be unplugged and moved away. Later in the evening, the first stage will be loaded with its 25,000 gallons of storable RP-1 propellant, a highly refined kerosene fuel.The latest launch weather forecast, issued this morning by the 45h Weather Squadron at Cape Canaveral, now indicates only a 20 percent chance of meeting the launch weather criteria on Monday. Strong ground winds, gusting to 35 knots, are the primary concern.Weather for the backup launch opportunity on Tuesday is 95 percent favorable with the winds diminishing significantly.Our live countdown updates will begin on this page at 12:30 a.m. EST (0530 UTC).
Happy Saturday. Looking forward to going to space shortly. LWO is forecasting some high winds in the window. So, everybody think calm thoughts.
https://twitter.com/ulalaunch/status/1999872352642064585QuoteRollout is underway of the United Launch Alliance Atlas V rocket to send the next batch of Amazon Leo broadband satellites into space Monday. Liftoff of the Leo 4 mission is planned for 3:49 a.m. EST (0849 UTC). Quote from: Live UpdatesThe MLP has been lowered onto the launch pad piers, accomplishing the "harddown" milestone at 11:51 a.m. EST. Over the next few hours today, umbilical connections will be made with launch pad systems, the environmental control system feeding conditioned air to the rocket and payload will be switched to facility supplies to allow the portable trailers used during rollout to be unplugged and moved away. Later in the evening, the first stage will be loaded with its 25,000 gallons of storable RP-1 propellant, a highly refined kerosene fuel.The latest launch weather forecast, issued this morning by the 45h Weather Squadron at Cape Canaveral, now indicates only a 20 percent chance of meeting the launch weather criteria on Monday. Strong ground winds, gusting to 35 knots, are the primary concern.Weather for the backup launch opportunity on Tuesday is 95 percent favorable with the winds diminishing significantly.Our live countdown updates will begin on this page at 12:30 a.m. EST (0530 UTC).
PLANNED LAUNCH/REENTRY:SPACEX STARLINK 15-12, VANDENBERG SFB, CAPRIMARY: 12/14/25 0520Z-1002ZBACKUP: 12/16/25 0452Z-0934ZSPACEX STARLINK 6-82, CAPE CANAVERAL SFS, FLPRIMARY: 12/15/25 0243Z-0726ZBACKUP: 12/16/25 0217Z-0700ZULA KA-04, CAPE CANAVERAL SFS, FLPRIMARY: 12/15/25 0835Z-1204ZBACKUP: 12/16/25 0813Z-1142ZSPACEX STARLINK 6-99, KENNEDY SPACE CENTER, FLPRIMARY: 12/15/25 1311Z-1754ZBACKUP: 12/16/25 1245Z-1728Z
Quote from: StraumliBlight on 12/13/2025 07:41 pmQuoteRollout is underway of the United Launch Alliance Atlas V rocket to send the next batch of Amazon Leo broadband satellites into space Monday. Liftoff of the Leo 4 mission is planned for 3:49 a.m. EST (0849 UTC). Quote from: Live UpdatesThe MLP has been lowered onto the launch pad piers, accomplishing the "harddown" milestone at 11:51 a.m. EST. Over the next few hours today, umbilical connections will be made with launch pad systems, the environmental control system feeding conditioned air to the rocket and payload will be switched to facility supplies to allow the portable trailers used during rollout to be unplugged and moved away. Later in the evening, the first stage will be loaded with its 25,000 gallons of storable RP-1 propellant, a highly refined kerosene fuel.The latest launch weather forecast, issued this morning by the 45h Weather Squadron at Cape Canaveral, now indicates only a 20 percent chance of meeting the launch weather criteria on Monday. Strong ground winds, gusting to 35 knots, are the primary concern.Weather for the backup launch opportunity on Tuesday is 95 percent favorable with the winds diminishing significantly.Our live countdown updates will begin on this page at 12:30 a.m. EST (0530 UTC).Weather forecast details:
QuoteRollout is underway of the United Launch Alliance Atlas V rocket to send the next batch of Amazon Leo broadband satellites into space Monday. Liftoff of the Leo 4 mission is planned for 3:49 a.m. EST (0849 UTC). Quote from: Live UpdatesThe MLP has been lowered onto the launch pad piers, accomplishing the "harddown" milestone at 11:51 a.m. EST. Over the next few hours today, umbilical connections will be made with launch pad systems, the environmental control system feeding conditioned air to the rocket and payload will be switched to facility supplies to allow the portable trailers used during rollout to be unplugged and moved away. Later in the evening, the first stage will be loaded with its 25,000 gallons of storable RP-1 propellant, a highly refined kerosene fuel.The latest launch weather forecast, issued this morning by the 45h Weather Squadron at Cape Canaveral, now indicates only a 20 percent chance of meeting the launch weather criteria on Monday. Strong ground winds, gusting to 35 knots, are the primary concern.Weather for the backup launch opportunity on Tuesday is 95 percent favorable with the winds diminishing significantly.Our live countdown updates will begin on this page at 12:30 a.m. EST (0530 UTC).
The launch of a United Launch Alliance Atlas V carrying the @AmazonLeo 4 mission is now planned for Tuesday, Dec. 16, at 3:28 a.m. EST at the opening of a 29-minute window. Teams are actively monitoring the weather and the forecasted winds during our original launch window present only a five percent chance of acceptability. The forecast for Dec. 16 provides a 95 percent chance of acceptable weather for launch.
The U.S. Space Force weather squadron at Cape Canaveral predicts a 95 percent chance of acceptable weather for the United Launch Alliance Atlas V rocket launch of the Amazon Leo mission on Tuesday at 3:28 a.m. EST (0828 UTC).
ULA@ulalaunch·Both launch weather and space weather are GO for the overnight Atlas V rocket launch at 3:28 a.m. EST (0828 UTC), according to the day's first weather briefing by Space Force launch weather officer from the Space Launch Delta 45 weather squadron at Cape Canaveral.
Dec 15 22:35We are entering the final five hours in our countdown to launch. All continues to progress well.A pre-launch test of the rocket's guidance system is now in progress. Also underway are checks of the GPS Metric Tracking system used to follow the rocket as it flies downrange and a test of the S-band telemetry relay system.
Dec 15 23:00All systems remain "go" here at the Advanced Spaceflight Operations Center and at the launch pad as we count down to tonight's Atlas V launch at 3:28 a.m. EST (0828 UTC). The weather is favorable and we are working no issues.At Space Launch Complex-41, the Atlas V rocket has undergone its flight control steering check of the engine nozzle gimbaling, and the flame bucket cover has been retracted and stowed for launch.
Welcome to the Atlas V countdown!From the Advanced Spaceflight Operations Center (ASOC) at Cape Canaveral Space Force Station in Florida, this is Atlas Launch Control at T-minus 2 hours and holding with 28 minutes remaining in this planned half-hour built-in hold prior to fueling.We are on schedule to launch an Atlas V 551 rocket carrying the Amazon Leo Atlas 4 (LA-4) broadband satellite mission to low Earth orbit today. Liftoff is targeted for 3:28 a.m. EST (0828 UTC) at the opening of a 29-minute launch window that extends to 3:57 a.m. EST (0857 UTC). The rocket, designated AV-111, will complete a single burn of the Centaur upper stage to reach an approximate 280-mile-high (450 km) orbit inclined 51.9 degrees. The Amazon Leo satellites are mounted atop the Atlas V attached to a special dispensing tower and will release at predetermined intervals, representing the most separation events performed in a single Atlas launch.This will be the 106th Atlas V rocket launch, continuing its eclectic mix of payloads and missions over a storied program life lasting more than 23 years. The launch pad crew recently completed its hands-on work to ready Space Launch Complex-41 for today's mission and Launch Conductor Scott Barney gave the instruction for personnel to depart the site in advance of fueling operations.Final preps are underway to begin cryogenic propellant loading operations for the Atlas-Centaur launch vehicle. The two stages will be filled with 66,000 gallons of liquid oxygen and liquid hydrogen once the countdown resumes. The ground transfer systems are configured for tanking operations and the environmental control system has completed its changeover from conditioned air to gaseous nitrogen flow to the Atlas V and the payload fairing in preparation for fueling and launch.We are not tracking any technical issues in the countdown and activities are progressing on the scheduled timeline. At T-minus 2 hours and holding, this is Atlas Launch Control.
Dec 16 00:05The missionUnited Launch Alliance today will launch the next grouping of operational satellites for Amazon Leo, formerly known as Project Kuiper.Amazon Leo is built around an initial constellation of more than 3,000 advanced low Earth orbit satellites. Its mission is to provide fast, reliable internet to customers and communities around the world, including those unserved or underserved by traditional connectivity technologies. The system has the capacity, performance, and flexibility to serve a wide range of customers, from individual households to schools, hospitals, businesses, government agencies and other organizations operating in places without reliable connectivity.Amazon Leo's satellite payloads are the heaviest Atlas V has ever flown. The payload is supported through attachment and reinforcement elements for the ride to orbit.ULA made several modifications and design changes to accommodate the mass and size of the missions. That included enhancements to the ground handling equipment needed to transport the encapsulated payload during the move from Amazon's satellite processing facility to ULA's Vertical Integration Facility and the hardware used to hoist the payload atop the Atlas V for connection.
Dec 16 00:08The launch team is controlling the countdown from the ASOC. The Cape also has assistance from design teams at ULA's Denver Operations Support Center, or DOSC. Once all of the satellites have separated from the rocket in space later today, the Amazon Leo team will take over constellation management from the 24/7 mission operations center in Redmond, Washington.
Dec 16 00:15The call to stations for cryogenic tanking has been announced to all console operators.The ground chilldown of the Atlas first stage liquid oxygen system is now underway and the pad's liquid oxygen tank for Centaur is being pressurized to chilldown levels.We are coming up on the readiness polls of the launch team to verify all systems are GO for fueling operations and at this time we are not working any technical issues that would preclude the start of tanking today.
Dec 16 00:20Weather remains 90% GOIn the pre-fueling weather briefing to mission management, the launch weather officer reports weather currently looks good for a rocket countdown. The radar is dry, winds are light and there are no weather constraints against proceeding into Atlas V fueling operations as scheduled.The launch time forecast remains unchanged with a 90 percent chance of acceptable conditions.The launch outlook continues to call for a few clouds, good visibility, northeasterly winds of 8-10 knots gusting to 15 knots and a temperature near 58 degrees F.
Dec 16 00:23This is Atlas Launch Control at T-minus 2 hours and holding, with five minutes remaining in the built-in hold. Launch Conductor Scott Barney is briefing console operators on procedures going forward in today's countdown and the proper method for reporting any issues. This operation is classified hazardous -- cryogenics will be loaded, ordnance items are installed and high-pressure and inert gases are in use.
Dec 16 00:25ULA Launch Director Don Malin is receiving status inputs on technical readiness from the ULA director of engineering and Amazon's spacecraft mission director, the results of which will feed into the readiness poll to authorize fueling to begin.
Dec 16 00:26Go for fuelingA readiness poll of the launch team by Launch Conductor Scott Barney, with concurrence of ULA Launch Director Don Malin, has approved cryogenic tanking operations to begin at the earliest opportunity once the countdown resumes.
Dec 16 00:28Countdown resumesThis is Atlas Launch Control at T-minus 2 hours (L-3 hours) and counting. The next phase of today's launch countdown has started on schedule as we continue to target 3:28 a.m. EST (0828 UTC) for liftoff of Amazon Leo 4 for the broadband constellation.Preparatory steps for fueling are being kicked off, including chilldown of the transfer lines to the Centaur upper stage liquid oxygen system.
Dec 16 00:33Let's take a look at the process of preparing the Atlas V rocket to reach this point in today's countdown to Amazon Leo 4. The high-performance variant of the legendary rocket family will deliver the 17-ton payload into orbit, helping to connect the world one launch at a time.
Dec 16 00:42Centaur LO2 loading beginsCentaur propulsion console operators here at the Launch Control Center have begun procedures to load the cryogenic propellants into Atlas V for today's Amazon Leo Atlas-4 mission.This first step is fueling will see about 4,150 gallons of liquid oxygen filling the Centaur upper stage for today's launch.
Dec 16 00:47While today's Atlas V launch has plenty of similarities to the previous Amazon flights, it is no less significant. The Leo Atlas 4 (LA-4) mission will mark another step to deploy an advanced broadband constellation in low Earth orbit (LEO).Like the successful Atlas V Kuiper 1 mission on April 28, Kuiper 2 on June 23 and Kuiper 3 on Sept. 25, which delivered Amazon's first operational spacecraft into LEO, the upcoming LA-4 mission will launch another batch of 27 satellites into space.The same Atlas V rocket configuration will be used as the inaugural missions -- with five side-mounted GEM 63 solid rocket boosters, a 17.7-foot-diameter (5.4m) composite payload fairing and single upper stage engine.And we will be flying the same flight profile to reach the targeted a 51.9-degree, 280-mile-high (450 km) low Earth orbit.
Dec 16 00:52Atlas LO2 loading beginsFilling of the Atlas V rocket's largest tank has begun. About 48,800 gallons of super-cold oxidizer for the main engine is flowing into the liquid oxygen tank on common core booster first stage.
Dec 16 00:53Now 30 percent of the Centaur LOX tank has been filled. The liquid oxygen -- chilled to Minus-298 degrees F -- will be consumed during the launch by the Centaur's single RL10C-1-1 engine along with liquid hydrogen to be pumped into the stage a little later in the countdown.
Dec 16 01:01The Centaur upper stage's liquid oxygen tank has reached the 75 percent level as filling continues.The chilldown conditioning of liquid hydrogen propellant lines at Space Launch Complex-41 is starting to prepare the plumbing for transferring the Minus-423-degree F fuel into the rocket.
Dec 16 01:04First stage liquid oxygen tank loading is transitioning from slow-fill to fast-fill mode.
Dec 16 01:08The Centaur liquid oxygen tank is topping to flight level.
Dec 16 01:11The first stage liquid oxygen tank has reached the 20 percent mark already.
Mission ProfileA delicate balance of brute force and precision is needed when launching a 17-ton payload into orbit Amazon's broadband constellation. That is what the Atlas V 551 rocket will deliver when it performs the Amazon Leo Atlas 4 (LA-4) mission.
Dec 16 01:21First stage liquid oxygen tank is 50 percent full thus far. The LOX will be consumed along with RP-1, a highly refined kerosene, by the RD-180 main engine on the first stage during the initial four minutes of flight. The 25,000 gallons of RP-1 were loaded into the rocket after rollout on Saturday.
Dec 16 01:28We are passing Launch Minus-2 hours in the countdown. Tanking operations are proceeding nominally after beginning at the earliest opportunity in our timeline today. All activities remain on schedule for a liftoff at 3:28 a.m. EST (0828 UTC).
Dec 16 01:32Centaur LH2 loading beginsThe launch team has received the "go" to begin filling the Centaur upper stage with the super-cold liquid hydrogen fuel following chilldown of the system. The Centaur holds about 12,300 gallons of the cryogenic propellant.
Dec 16 01:37Centaur engine chilldown has begun to condition the RL10. Liquid nitrogen will be used to cool the engine pumps to the proper temperatures for flight
Dec 16 01:40Flight control final preps are getting underway. This is the steering test pattern run on the Atlas V engine nozzles to ensure proper gimbaling during the ascent.
Dec 16 01:42Filling of the first stage liquid oxygen tank has been completed. Topping mode is now underway.
Dec 16 01:44Centaur's liquid hydrogen tank is 50 percent full. The cryogenic propellant will be consumed with liquid oxygen by the stage's Aerojet Rocketdyne RL10C-1-1 engine.
Dec 16 01:48If you are just tuning in, the countdown is proceeding toward a liftoff of AV-111 at 3:28 a.m. EST (0828 UTC) on the Amazon Leo Atlas 4 (LA-4) mission. We continue to have a smooth countdown with no issues being worked that would stand in the way of liftoff.
Dec 16 01:55Filling of the Centaur upper stage liquid hydrogen tank has been completed. Topping mode is now underway to give us a rocket weighing 1.29 million pounds (587,000 kg) for launch. The cryogenics will be replenished throughout the countdown until the final minutes before launch to replace the liquid oxygen and liquid hydrogen that naturally boils away.
Dec 16 02:10The countdown is continuing smoothly towards liftoff from Cape Canaveral.Ascending from Space Launch Complex-41, the Atlas V will immediately execute pitch, yaw and roll maneuvers to align with a northeasterly heading for its 18-minute climb into a 51.9-degree, 280-mile-high (450 km) orbit. Centaur will perform a single burn with guidance-commanded shutdown enabled to reach the precise injection parameters required by our customer.
Dec 16 02:16Today's launch comes as the Atlas V rocket marks 23 years in service. The launch system has demonstrated unmatched reliability since 2002, successfully launching scientific spacecraft to Mars on five different occasions, plus research investigations to the Sun, the Moon, Jupiter, the Asteroid Bennu and Pluto -- all with bullseye trajectories every time.The rocket's versatility also has delivered dozens of U.S. national security assets into space, launched weather observatories that all Americans depend upon and deployed commercial satellites to connect the world.The eclectic mix of payloads and missions even spans to human spaceflight by serving as the launch vehicle for two NASA astronauts last year.
Dec 16 02:24Countdown holdingT-minus 4 minutes and holding. The countdown has entered the planned 60-minute built-in hold designed to give a bit of margin to ensure we are ready for terminal count. During this pause, the final readiness polls of the launch team and management members will be performed. The hold duration also syncs the countdown with our target launch time.We remain on schedule for a liftoff at 3:28 a.m. EST (0828 UTC) from Space Launch Complex-41 at Cape Canaveral.
Dec 16 02:28Meet Amazon LeoAmazon Leo is Amazon's low Earth orbit satellite constellation.The network is built around an initial constellation of more than 3,000 satellites in low Earth orbit. Amazon plans to expand the constellation over time, extending coverage to virtually any location on the planet.Amazon Leo is designed with the capacity, flexibility, and performance to serve a wide range of customers, from individual households to schools, hospitals, businesses, government agencies, and other organizations operating in locations without reliable connectivity.There are billions of people on the planet who lack access to high-speed internet, and millions of businesses, governments and other organizations operating in places without reliable connectivity. The Amazon Leo mission is to help bridge that gap by delivering fast, reliable internet to customers around the world.Amazon is investing an initial $10 billion to deploy Amazon Leo. There are currently thousands of people at Amazon working on the program, and multiple facilities to support production and operations, including a dedicated satellite production facility in Kirkland, Washington, and a dedicated satellite processing facility at Kennedy Space Center in Florida.
Dec 16 02:35ULA rocket factory tourOur journey to space begins in Decatur, Alabama at ULA's 2.2M square foot rocket factory. Long before the path to orbit, the missions start on the factory floor.
Brevard EOC@BrevardEOC12/16/25 2:30 AM | We have activated our launch operations support team in preparation for the @ulalaunch Atlas V launch. Window: 3:28 - 3:57 AM
Dec 16 02:40Communications channels here in the Advanced Spaceflight Operations Center are quiet as console operators monitor their systems during this built-in hold. No significant issues are being worked at the present time.
Dec 16 02:43The Atlas V, designated AV-111, is a two-stage rocket that incorporates five GEM 63 solid rocket boosters, features a single RL10C-1-1 engine on the Centaur upper stage and encapsulates the spacecraft in a 5.4-meter-diameter (17.7-foot) payload fairing. It stands 205 feet (62.5 meters) tall and will leave the pad on 2.7 million pounds (12 megaNewtons) of thrust from the kerosene-fueled first stage main engine and solid motors.The Atlas V 551 is the highest performance configuration of the rocket family with a full complement of five solid rocket boosters. It first flew in 2006 and has launched the New Horizons spacecraft to Pluto, the Juno orbiter to Jupiter, a variety of national security missions and now several Amazon missions.
Dec 16 02:49This is Atlas Launch Control at T-minus 4 minutes and holding, with 35 minutes remaining in this programmed hour-long hold.The launch team is not working any significant issues in the countdown that would preclude an on-time liftoff of the Atlas V rocket today.Our 29-minute launch opportunity opens at exactly 3:28 a.m. EST (0828 UTC) and extends to 3:57 a.m. EST (0857 UTC). The launch window is determined by Atlas V satisfying the requirements to deliver this grouping of Amazon Leo satellites into the desired low Earth orbit.
Dec 16 02:58L-30 minutesNow standing by for the final pre-flight weather assessment from the Space Force's launch weather officer.We are a half-hour away from our high-performance Atlas V 551 rocket heading to space carrying the next batch of Amazon Leo satellites. The launch team is not tracking any technical issues at this time.
Dec 16 02:59Weather is GOWeather is observed and forecast GO for liftoff a half-hour from now, according to the countdown's final planned briefing by the launch weather officer.
Dec 16 03:01The Automatic Determination and Dissemination of Just Updated Steering Terms, better known as the ADDJUST file, is being loaded into the Atlas V rocket's Inertial Navigation and Control Assembly (INCA) flight computer by the flight control operator here at the Launch Control Center.This is the planned steering parameters for the INCA to use based on today's upper level wind conditions.A series of weather balloons has been launched throughout the countdown from the Range weather station at the Cape to collect measurements of wind speeds and directions to determine if conditions aloft violate the controllability or structural loads on the rocket during ascent. The balloon data was transmitted to ULA engineers in Denver to select a steering profile that minimizes launch vehicle responses.
Dec 16 03:02The fuel fill sequence is beginning. This procedure releases RP-1 kerosene fuel into the RD-180 main engine in preparation for ignition.
Dec 16 03:03Our visibility graphic shows when the Atlas V rocket will rise into view for spectators across Florida and the Eastern Seaboard today. This nighttime launch should be visibile for hundreds of miles around.
Dec 16 03:05The live video broadcast of today's liftoff is about to begin in the embedded YouTube stream on this page.
Dec 16 03:08Now 20 minutes away from the opening of today's 29-minute launch window for Atlas V to take flight with Leo 4.Here's some key facts and figures about Amazon Leo. The initial constellation size is more than 3,000 satellites in low Earth orbit. The initial constellation will cover areas between 56 degrees north and south of the equator. Amazon Leo plans to expand the constellation over time, extending coverage to virtually any location on the planet.As for performance, the enterprise-grade terminal (Leo Ultra) will provide downlink speeds up to 1 Gbps. The compact, high-performance terminals – Leo Pro and Leo Nano – will provide downlink speeds up to 400 Mbps and 100 Mbps, respectively.Amazon Leo will connect tens of millions of customers around the world.
Dec 16 03:09Upper-level winds have been verified acceptable for launch.
Dec 16 03:11In the countdown, we have completed the fuel fill sequence to ready the first stage main propulsion system for launch.
Dec 16 03:12Status continues to be green across the board. Weather remains in our favor this morning, no technical issues are being addressed with the launch vehicle or pad systems and we are on schedule for liftoff.
Dec 16 03:13This is Atlas Launch Control, now passing L-minus 15 minutes for the Atlas V rocket and Amazon Leo, the low Earth orbit satellite broadband network. Its mission is to provide fast, reliable internet to customers around the world, including those in unserved and underserved communities, using a constellation of more than 3,000 LEO satellites.
Dec 16 03:14Vehicle Systems Engineer is polling the Denver technical team comprised of specialists in the various hardware and technology disciplines on the Atlas V. The experts have conducted evaluation of rocket data and systems performance throughout the countdown.The results of this poll will be routed to the ULA director of engineering, who will then supply his readiness to launch when polled by the ULA launch director.
Dec 16 03:16In just a few minutes, you'll hear ULA Launch Conductor Scott Barney, from his console in the Advanced Spaceflight Operations Center, perform the readiness poll to enter terminal count."The primary responsibility for the launch conductor (LC) is to lead the launch team to liftoff. The LC orchestrates the launch flow, allowing the individual systems operators to focus on their detailed tasks," Barney says."Much of this work is planned in advance of launch day with the know mission unique specifics that impact the launch count. On launch day, the LC needs to assess real-time changes that impact the operation and determine a path forward to meet the limited window."This is Barney's 29th Atlas V launch as the mission's launch conductor. He also has done 23 Delta IV launches, a pair of Delta II missions and one Vulcan.
Dec 16 03:17ULA Launch Conductor Scott Barney has been notified by the Amazon spacecraft team that the payload has successfully switched to flight mode. This puts the Amazon Leo hardware atop the Atlas V into the correct launch configuration.At T-minus 4 minutes and holding with 7 minutes remaining in the built-in hold, this is Atlas Launch Control.
Dec 16 03:18We are just 10 minutes away from the next in our recurring launches dedicated to Amazon Leo. Our mission is to launch critical payloads for our customers and serve as the catalyst to help Amazon build this global broadband constellation aligning us with one of our core missions of connecting the world.ULA will perform 46 launches for Amazon using our high-performance variants of Atlas V and Vulcan rocket to deploy a majority of the advanced broadband satellite constellation in low Earth orbit.
Dec 16 03:19The launch conductor is reminding all console operators that if a constraint is observed after the L-minus 7 minute readiness poll, the team member shall announce "hold, hold, hold" on the communications loops, identify their station and briefly state the reason for the hold.
Dec 16 03:20We are standing by for the readiness poll to proceed with the terminal count. Launch Conductor Scott Barney will poll the collective team for the "go" to launch today.Right now, Launch Director Don Malin is receiving status inputs on technical readiness from the ULA director of engineering and Amazon spacecraft mission director, the results of which will feed into the readiness poll.
Poll for terminal countPolling is underway to proceed with terminal count. The ULA launch conductor is performing this status check of more than two dozen console operators and mission leaders to ensure all systems are ready to continue with the countdown to liftoff.
Dec 16 03:22GO for launch!The ULA Launch Director Don Malin has given final permission to launch.The pronouncement was made following the readiness poll of the launch team by Launch Conductor Scott Barney that verified all systems are "go" to resume the countdown.
Dec 16 03:23L-minus 5 minutes. Standing by to pick up the countdown clocks once again.
Dec 16 03:24Countdown resumesT-minus 4 minutes and counting. The final phase of today's countdown is underway at Cape Canaveral to launch the Atlas V rocket with Amazon Leo 4. The countdown clocks have resumed, leading us to liftoff.
Dec 16 03:25T-minus 3 minutes and counting. The Atlas first stage liquid oxygen replenishment is being secured so that the tank can be pressurized for launch. And the ground pyrotechnics have been armed to release the vehicle from the launch pad at liftoff.
Dec 16 03:26T-minus 1 minute, 55 seconds. The start command has been issued to the launch sequencer. The sequencer will perform independent verifications of systems for the rest of the countdown, control the detachment of umbilicals from the vehicle and release the rocket from the pad at liftoff. The first stage RP-1 kerosene fuel and the liquid oxygen tanks have stepped up to proper pressure levels for flight and the Atlas and Centaur stages have switched from ground power to internal batteries. In the next few seconds, the liquid oxygen and liquid hydrogen propellant topping to the Centaur upper stage will be secured and the tanks go be confirmed stable at flight pressures.
Dec 16 03:26T-minus 80 seconds. The rocket's ordnance controller and the vehicle safety system have been armed. The flight software on the Atlas V is going active at this time.
Dec 16 03:27T-minus 55 seconds. The firing chain is armed. The solid rocket boosters are ready for ignition.The Range Operations Commander confirms that the Eastern Range at the Cape is in a "green" condition for launch.Coming up at T-minus 25 seconds, a final status check will be announced on Atlas, Centaur and payload readiness by each stage's prop lead engineer and the launch conductor. The RD-180 will roar to life at T-minus 2.7 seconds. Once the engine ready indication is received, the solid rocket boosters will light and hold down bolts fired to release the vehicle from the pad for liftoff at T+plus 1.1 seconds.
Dec 16 03:28LIFTOFF!Liftoff of the United Launch Alliance Atlas V rocket and the next satellites for Amazon Leo to enhance broadband access and connect the world!
Dec 16 03:28T+plus 30 seconds. Speed 450 mph already. A good roll maneuver is complete for Atlas V, putting the rocket on the proper northeasterly heading for its 18-minute trip to reach a 51.9-degree low Earth orbit. The rocket's main engine and solid rocket boosters are providing 2.7 million pounds (12 megaNewtons) of thrust.
Dec 16 03:29T+plus 60 seconds. Atlas V is 9 miles in altitude and the main engine has throttled as programmed to minimize aerodynamic loads while the full complement of five side-mounted solid rocket boosters provides two-thirds of the launch power.The rocket has broken through the sound barrier to go supersonic and passed the region of maximum aerodynamic stresses in the lower atmosphere.
Dec 16 03:29T+plus 1 minute, 35 seconds. We have solid rocket booster burnout as Atlas V accelerates over 3,000 mph. Jettison will occur once aerodynamic conditions are met a few seconds from now.
Dec 16 03:29SRB separationT+plus 1 minute, 50 seconds. Solid rocket booster jettison is confirmed at an altitude of 30 miles. The GEM 63 motors have successfully separated from the Atlas V first stage, having completed their job.The five GEM 63s have consumed a half-million pounds (227,000 kg) of propellant to augment the initial liftoff power of the Atlas V. The rocket now weighs half of what it did at liftoff less than two minutes ago.
Dec 16 03:30T+plus 2 minutes. Atlas V is transiting to closed-loop guidance, following SRB separation, to aim the trajectory towards a precise point in space.The rocket continues towards orbit on the power of its main engine and will more than triple its speed in the two minutes remaining in first stage flight.
Dec 16 03:30T+plus 2 minutes, 30 seconds. Atlas V is more than 50 miles in altitude, 65 miles downrange from the launch pad, traveling over 5,000 mph. The main engine operating parameters are nominal as it burns a mixture of highly refined kerosene and liquid oxygen.
Dec 16 03:31T+plus 3 minutes. Atlas V has exited Earth's atmosphere and crossed the Karman line as velocity accelerates beyond 6,000 mph. The rocket now weighs just one-quarter of its liftoff mass.The main engine is throttling to maintain a constant acceleration in preparation for payload fairing separation.And pyro valve opening is confirmed on the Centaur, allowing helium to pressurize the reaction control system for its upcoming use.
Dec 16 03:32T+plus 4 minutes. The Atlas V main engine continues to burn well and vehicle hydraulics are operating as expected.The engine is again throttling now to maintain a constant acceleration limit as first stage flight nears its conclusion. The Centaur is about to begin its cooldown sequence during the boost-phase of flight in preparation for RL10 ignition.
Dec 16 03:32StagingT+plus 4 minutes, 49 seconds. Successful Atlas staging is confirmed as the rocket passes off the coast of Cape Hatteras, North Carolina at an altitude of 140 miles. The first stage of flight was completed with booster engine cutoff, or BECO, followed by separation of the Atlas V's common core booster. The vehicle now weighs less than seven percent of its liftoff mass. The Centaur upper stage will continue the ascent by firing its RL10C-1-1 cryogenic engine for 13 minutes to accelerate the Amazon Leo payload into the planned low Earth orbit.
ULA@ulalaunchSuccessful Atlas staging is confirmed as the rocket passes off the coast of Cape Hatteras, North Carolina at an altitude of 140 miles. The Centaur upper stage continues the ascent by accelerating the Amazon Leo payload to orbit. The vehicle now weighs less than seven percent of its liftoff mass. http://bit.ly/av_leo4
Dec 16 03:34T+plus 6 minutes. Atlas V is now appearing as a bright star, streaking through the eastern sky of New York City. The rocket is 200 miles in altitude as it powers towards orbit.The RL10C-1-1 parameters continue to operate as expected. The engine is firing to lift the rocket the rest of the way to orbital velocity. This burn by Centaur will place the vehicle into a near-circular low Earth orbit of 280 miles (450 km) at an inclination of 51.9 degrees around the Earth.
Dec 16 03:36T+plus 8 minutes, 30 seconds. Atlas V is now in the skies of Halifax, Nova Scotia, moving at 12,800 mph. Centaur continues to progress in its single burn of the Amazon Leo Atlas 4 (LA-4) mission, consuming liquid hydrogen and liquid oxygen propellants. Telemetry indicates good performance.
Dec 16 03:38T+plus 10 minutes. Atlas V remains on course and transmitting good quality data as it travels over 13,000 mph above the North Atlantic.Engine continues to operate as expected. Less than eight minutes remain in powered flight.
Dec 16 03:39T+plus 11 minutes. Now streaking 290 miles in altitude and east of Newfoundland. The RL10 engine continues to operate as expected and body rates of the upper stage are normal. For the past sixty years, Centaurs and the RL10 engine has played a vital role in placing hundreds of military, government and commercial satellites into Earth orbit and has helped send spacecraft to explore every planet in our solar system.ULA also uses RL10 on the Centaur V for Vulcan and the Interim Cryogenic Propulsion Stage supplied to NASA's Artemis program.
Dec 16 03:40T+plus 12 minutes. Atlas V is now 2,000 miles northeast of the launch pad, traveling more than 14,000 mph.A check of Centaur telemetry shows good engine performance and nominal body rates. The vehicle continues in this burn to obtain orbit around the Earth.
Dec 16 03:42T+plus 14 minutes. Just under four minutes of powered flight remains. Atlas V is traveling more than 15,000 mph.The venerable Centaur upper stage -- with a thin-walled, less than the thickness of a dime -- is a stainless steel pressure-stabilized structure that provides the most weight-efficient stage possible.The stage has evolved considerably from its early days, becoming more capable, more powerful and more accurate. But the overall Centaur stage architecture today is fundamentally the same concept as the versions flown in the early 60s.
Dec 16 03:43T+plus 15 minutes. Atlas V is high above the central North Atlantic, having left its launch pad in Floria just one quarter-of-an-hour ago. Centaur systems remain in good shape as the stage continues to power toward orbit with the next 27 satellites of Amazon Leo.
Dec 16 03:44T+plus 16 minutes. The Amazon Leo payloads are the heaviest ever carried by Atlas V at 34,000 pounds (15,400 kg). The satellites ride into space attached to a special dispensing tower and release at predetermined intervals, representing the most separation events ever performed in a single Atlas launch.
Dec 16 03:45T+plus 17 minutes. Atlas V is now orbital. Standing by to conclude this Centaur burn once the desired deploy orbit is reached.
Dec 16 03:45MECOT+plus 17 minutes, 22 seconds. Main engine cutoff, or MECO, is confirmed for the Centaur upper stage. The Atlas V rocket has achieved its low Earth orbit with the Amazon Leo Atlas 4 mission.
Dec 16 03:48To recapThis will conclude live coverage of today's countdown and liftoff of the Atlas V rocket on its fourth Amazon Leo mission from Cape Canaveral, Florida.To recap, the United launch Alliance rocket departed Space Launch Complex-41 at 3:28 a.m. EST to deliver into orbit the next 27 satellites for the low Earth orbit constellation.The countdown started at 7:38 p.m. EST under the guidance of Launch Conductor Scott Barney. A "go" for cryogenic propellant loading was given by ULA Launch Director Don Malin and tanking operations were successfully performed as 66,000 gallons of liquid hydrogen and liquid oxygen were placed into the rocket.The clear to launch poll was performed at 3:21 a.m. EST to enter terminal count, which resulted in liftoff at the opening of the launch window.Today's launch is the fourth of 46 recurring missions for Amazon Leo. Amazon is partnering with ULA to launch a majority of its constellation using a total of eight Atlas V and 38 Vulcan rockets under the largest commercial launch services agreement in industry history.Amazon Leo is built around an initial constellation of more than 3,000 advanced low Earth orbit satellites. Its mission is to provide fast, reliable internet to customers and communities around the world, including those unserved or underserved by traditional connectivity technologies. The system has the capacity, performance, and flexibility to serve a wide range of customers, from individual households to schools, hospitals, businesses, government agencies and other organizations operating in places without reliable connectivity.
Wow, SRBs separation really kicked off ice/sparks.
William Harwood@cbs_spacenewsA5/LEO 4: Assuming all goes well with today's launch, Amazon will have put 180 Leo sats in orbit using 4 United Launch Alliance Atlas 5s (27 Leos each) and 3 SpaceX Falcon 9s (24 Leos each); today's launch was the 4th of 46 Leo flights planned by ULA using 8 Atlas 5s and 38 Vulcan rockets
The lawn chair next to the flame trench is one of my favorite views.
United Launch Alliance (ULA) successfully deployed another batch of Amazon Leo satellites into orbit at 3:28 a.m. EST on Tuesday, December 16th. Named LA-04 for Amazon’s fourth launch on a ULA Atlas V rocket, the mission added 27 satellites to the constellation, bringing the total number of Amazon Leo spacecraft launched to date to 180 satellites.Atlas V deployed the satellites at an altitude of 289 miles (465 kilometers) above Earth, at which point the Amazon Leo team took over command of the mission from our mission operations center in Redmond, Washington. From there, we perform initial satellite health checks and prepare to raise the satellites to their assigned altitude of 392 miles (630 km), where they will be fully commissioned as part of our operational satellite constellation.LA-04 marks our seventh successful launch this year, and our first as Amazon Leo. These missions have allowed us to deploy enough satellites to begin an enterprise preview for select business and government customers, and we plan to roll out service more broadly as we add coverage and capacity to the network. We’re continuing to increase production, processing, and launch rates as we look ahead to a higher cadence of missions next year, and will have more to share on subsequent missions as they approach.
ULA@ulalaunchRocket science in motion. United Launch Alliance delivers for @AmazonLeo once again. http://bit.ly/av_leo4
Amazon Leo@AmazonleoDeployment confirmed: 27 more Amazon Leo satellites have been added to our constellation and are operating nominally on orbit. Thanks to @ulalaunch for a fourth successful launch on Atlas V.
