Prepare for a launch doubleheader tonight: A United Launch Alliance Atlas V rocket and a SpaceX Falcon 9 rocket should lift off back-to-back from Florida’s Space Coast.

Welcome to FLORIDA TODAY Space Team live coverage of a unique Amazon Project Kuiper-Starlink launch doubleheader.

First, ULA is targeting 7:01 p.m. to launch the Atlas V — which is outfitted with five solid rocket boosters — and deploy the first production batch of 27 Project Kuiper broadband satellites into low-Earth orbit. The launch window lasts two hours, until 9 p.m., and the rocket will fly along a northeasterly trajectory from Cape Canaveral Space Force Station.

A few hours afterward, SpaceX is targeting 10:31 p.m. to launch a Falcon 9 carrying 23 Starlink satellites from pad 39A at NASA’s Kennedy Space Center. That rocket will track to the southeast. Backup launch opportunities will remain available until 1:31 a.m. Tuesday, if needed.

No Central Florida sonic booms should occur during these missions. The Space Force’s 45th Weather Squadron now predicts odds of favorable weather have increased to 80% for ULA’s liftoff, with meteorologists keeping an eye on “the risk of electrically-charged anvil clouds from thunderstorms that could develop later today in Central Florida.”

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When ULA’s live webcast begins about 6:35 p.m., look for it posted below next to our countdown clock. After liftoff, we’ll continue our launch doubleheader coverage on this page through SpaceX’s Starlink launch attempt. 

Cape Canaveral: Is there a launch today? Upcoming SpaceX, NASA rocket launch schedule at Cape Canaveral

Atlas V solid rocket boosters jettison

Update 7:05 p.m.: ULA officials confirmed that the five solid rocket boosters have separated.

“T+plus 1 minute, 50 seconds. Solid rocket booster jettison is confirmed. The Northrop Grumman-made GEM 63 motors have successfully separated from the Atlas V first stage, having completed their job,” a ULA update said.

“Atlas V will soon transition to closed-loop guidance, following SRB separation, to aim the trajectory towards a precise point in space,” the update said.

“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,” the update said.

Liftoff!

Update 7:01 p.m.: Liftoff! The ULA Atlas V with five solid rocket boosters has lifted off from Cape Canaveral Space Force Station.

ULA: Atlas V rocket is ‘go for launch’

Update 6:57 p.m.: The final readiness poll results: “Go for launch.”

Liftoff is scheduled in four minutes.

Nine minutes before Atlas V liftoff from Cape

Update 6:52 p.m.: The ULA launch countdown continues proceeding toward liftoff.

“Kuiper 1 will mark the 250th flight of a Centaur upper stage on an Atlas rocket. The Atlas Centaur combination has successfully launched spacecraft across the solar system, including 8 trips to Mars, delivered dozens of other scientific and weather satellites, carried critical assets into space for U.S. national security, and enabled commercial missions including launching astronauts in support of NASA’s Commercial Crew Program,” a ULA update said.

Atlas V rocket fully fueled for launch

Update 6:48 p.m.: ULA just reported all three Atlas V cryogenic tanks have been topped off to flight level.

“Upper level winds have been verified acceptable for launch,” a ULA update said.

Rocket launch target time moved to 7:01 p.m.

Update 6:42 p.m.: ULA has pushed back the target launch time one minute, to 7:01 p.m.

This Atlas V graphic depicts potential visibility for launch spectators across much of the eastern United States, ranging from 30 seconds to 6½ minutes after liftoff along the ascending rocket’s flight path.

ULA Project Kuiper launch webcast begins

Update 6:35 p.m.: ULA’s launch webcast is now posted above, right below our countdown clock.

Liftoff is scheduled in 25 minutes from Cape Canaveral Space Force Station.

Will cumulus cloud cause a launch delay?

Update 6:28 p.m.: A cumulus cloud off the Atlantic Ocean is approaching Launch Complex 41, ULA officials warned six minutes ago.

“The weather team is interrogating the cumulus cloud coming off the ocean and headed toward the pad. It likely would cause a NO GO status on the weather,” a ULA update said.

Atlas V Centaur liquid hydrogen filling is complete

Update 6:20 p.m.: ULA announced the Centaur upper-stage liquid hydrogen tank is filled ahead of launch.

“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,” a ULA update said.

ULA Atlas V launch prep underway in Brevard

Update 6:10 p.m.: Brevard County Emergency Management officials have activated the agency’s launch operations support team ahead of ULA’s upcoming Atlas V launch.

ULA making 2nd Atlas V launch try after April 9 scrub

Update 6 p.m.: As a reminder, this Amazon Project Kuiper mission was initially scheduled to lift off nearly three weeks ago, on April 9.

However, cumulus clouds kept encroaching the 10-mile safety ring surrounding Launch Complex 41. And the launch got scrubbed.

Odds of ‘go for launch’ weather increase to 80%

Update 5:51 p.m.: In a significant update, the 45th Weather Squadron has upped the odds of favorable launch weather from 70% to 80% when the two-hour window opens at 7 p.m.

Those odds dip to 65% by the end of the launch window. In a 5:40 p.m. tweet, ULA President and CEO Tory Bruno noted that an anvil cloud is approaching the Cape.

“L- 1hr 22 min. Board is green. Working no issues. Wind is good. Anvil cloud heading our way. Everybody face west and aggressively exhale,” Bruno said.

ULA releases Atlas V Project Kuiper video

Update 5:45 p.m.: Check out ULA’s video below that details tonight’s upcoming mission. Fueling of the first-stage liquid oxygen tank has hit the 60% mark, ULA reported.

Amazon details Project Kuiper customer terminals

Update 5:35 p.m.: In a fact sheet, Amazon officials provided the following descriptions of the three primary customer terminals for the future Project Kuiper satellite internet network:

• Our compact model is less than 11 inches square and delivers speeds up to 400 megabits per second (Mbps). We can produce it for less than $400 and expect to bring the cost down further.
• Our enterprise-grade model is a full-duplex antenna that measures 19 inches by 30 inches. It can deliver speeds up to 1 gigabit per second for demanding enterprise, government, and telecommunications applications.
• Our ultra-compact model is 7 inches square — about the size of a Kindle — and delivers speeds up to 100 Mbps.

Amazon launch to be 35th of year from Space Coast

Update 5:25 p.m.: ULA’s upcoming Atlas V launch will become the 35th orbital rocket launch thus far during 2025 from KSC and Cape Canaveral Space Force Station. A bit later, tonight’s SpaceX’s upcoming Falcon 9 liftoff will clock in at No. 36.

Click here for the FLORIDA TODAY Space Team’s updating log of these missions, complete with photo galleries and story links.

Atlas V rocket fueling is underway

Update 5:15 p.m.: ULA crews are loading about 4,150 gallons of liquid oxygen into the rocket’s Centaur upper stage.

“The liquid oxygen — chilled to Minus-298 degrees F — will be consumed during the launch by the Centaur’s single RL10A-4-2 engine along with liquid hydrogen to be pumped into the stage a little later in the countdown,” a ULA blog post said.

Amazon video explains Project Kuiper

Update 5:04 p.m.: Check out Amazon’s video below detailing Project Kuiper, the future constellation of 3,232 satellites in low-Earth orbit.

ULA crews preparing to fuel Atlas V rocket

Update 4:47 p.m.: The launch countdown is underway behind the scenes, and ULA reported that cryogenic tanking operations are expected to begin soon.

For the latest news and launch schedule from Cape Canaveral Space Force Station and NASA’s Kennedy Space Center, visit floridatoday.com/space.

Rick Neale is a Space Reporter at FLORIDA TODAY. Contact Neale at[email protected]. Twitter/X: @RickNeale1

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