The ubiquitous Global Positioning System that ties the space program to everyday life on Earth, providing precise navigation to the world through a constellation of orbiting satellites, will be strengthened courtesy of a new craft launched Wednesday.

Read our launch story.

1925 GMT (3:25 p.m. EDT)
The next Atlas 5 rocket launch is planned for the end of August from Cape Canaveral carrying the Navy's MUOS 4 mobile communications satellite.

For ULA, the company's next mission is a week away on July 22 when a Delta 4 rocket launches the Air Force's WGS 7 communications spacecraft.

1922 GMT (3:22 p.m. EDT)
MISSION SUCCESS DECLARED by United Launch Alliance officials.

The Centaur upper stage completed its second burn and released the Global Positioning System 2F-10 satellite into the navigation network to complete today's launch of the Atlas 5 rocket.

“Congratulations to the U.S Air Force and the entire mission team on today’s successful launch of the 10th GPS 2F satellite! In just a few days, on July 17, the Global Positioning System will celebrate the 20th anniversary of GPS achieving fully operational status,” said Jim Sponnick, ULA vice president, Atlas and Delta Programs.

“ULA is very proud to play a role in delivering these satellites to orbit, with Atlas and Delta rockets having launched all 58 operational GPS satellites.”

1628 GMT (12:28 p.m. EDT)
VIDEO REPLAY of today's Atlas 5 rocket launch with the GPS 2F-10.
1555 GMT (11:55 a.m. EDT)
We will pause our live updates at this time. Check back later for confirmation of the second Centaur burn and deploy of the GPS 2F-10 satellite to complete today's mission.
1553 GMT (11:53 a.m. EDT)
T+plus 17 minutes, 14 seconds. MECO 1. Centaur's main engine has shut down following its first burn today, achieving a transfer orbit to reach the GPS network around Earth. The rocket will coast in this orbit for about 3 hours before the RL10 engine re-ignites to circularize the orbit and then deploys the satellite.
1552 GMT (11:52 a.m. EDT)
T+plus 16 minutes, 10 seconds. Everything looking normal with one minute to go in this burn.
1551 GMT (11:51 a.m. EDT)
T+plus 15 minutes, 30 seconds. RL10 engine parameters still look good.
1550 GMT (11:50 a.m. EDT)
T+plus 14 minutes, 30 seconds. The rocket traveling over 17,576 mph.
1549 GMT (11:49 a.m. EDT)
T+plus 13 minutes. Centaur remains on course and looking good.
1548 GMT (11:48 a.m. EDT)
T+plus 12 minutes, 15 seconds. About five minutes are left in this burn of Centaur.
1546 GMT (11:46 a.m. EDT)
T+plus 10 minutes. All systems reported stable as the Centaur fires to reach an initial Earth orbit.
1545 GMT (11:45 a.m. EDT)
T+plus 9 minutes. Centaur performance is reported right on target.
1543 GMT (11:43 a.m. EDT)
T+plus 7 minutes, 45 seconds. The rocket is tracking right down the planned flight path.
1541 GMT (11:41 a.m. EDT)
T+plus 5 minutes. Centaur engine readings look good as this burn gets underway.
1540 GMT (11:40 a.m. EDT)
T+plus 4 minutes, 37 seconds. The two halves of the four-meter-diameter Atlas 5 rocket nose cone encapsulating the spacecraft have separated.
1540 GMT (11:40 a.m. EDT)
T+plus 4 minutes, 25 seconds. Centaur has ignited! The RL10C-1 engine is up and running at full thrust to power the vehicle into orbit.
1540 GMT (11:40 a.m. EDT)
T+plus 4 minutes, 15 seconds. The Atlas 5's Common Core Booster has been jettisoned, completing the first stage of flight, and the Centaur upper stage's liquid hydrogen and liquid oxygen systems are being readied for engine start.
1540 GMT (11:40 a.m. EDT)
T+plus 4 minutes, 8 seconds. BECO. Booster Engine Cutoff is confirmed as the RD-180 powerplant on the first stage completes its burn. Standing by to fire the retro thrusters and separate the spent stage.
1539 GMT (11:39 a.m. EDT)
T+plus 3 minutes, 45 seconds. Atlas now weighs just a quarter of what it did at liftoff.
1538 GMT (11:38 a.m. EDT)
T+plus 2 minutes, 45 seconds. Reaction control system has been activated.
1538 GMT (11:38 a.m. EDT)
T+plus 2 minutes, 35 seconds. Atlas continues tracking on course.
1538 GMT (11:38 a.m. EDT)
T+plus 2 minutes, 30 seconds. Atlas now weighs half of what it did at liftoff.
1538 GMT (11:38 a.m. EDT)
T+plus 2 minutes, 15 seconds. Vehicle systems looking good.
1537 GMT (11:37 a.m. EDT)
T+plus 1 minutes, 45 seconds. The RD-180 main engine continues to fire normally, burning a mixture of highly refined kerosene and liquid oxygen.
1537 GMT (11:37 a.m. EDT)
T+plus 100 seconds. Now passing through the region of maximum aerodynamic pressure on the vehicle as its accelerates through the dense lower atmosphere.
1537 GMT (11:37 a.m. EDT)
T+plus 85 seconds. All looks good aboard Atlas as it passes Mach 1.
1537 GMT (11:37 a.m. EDT)
T+plus 60 seconds. One minute into the ascent of GPS 2F-10.
1536 GMT (11:36 a.m. EDT)
T+plus 40 seconds. The Atlas 5 is sending a thunderous roar across Florida's spaceport carrying the 10th Boeing-built GPS 2F navigation satellite.
1536 GMT (11:36 a.m. EDT)
T+plus 15 seconds. The Atlas 5 rocket has cleared the tower on 860,000 pounds of thrust from the RD-180 main engine. Pitch, yaw and roll maneuvers are underway to put the rocket on the proper heading.
1536 GMT (11:36 a.m. EDT)
LIFTOFF! Liftoff of the Atlas 5 rocket with the latest satellite for the Global Positioning System -- a marvel of the modern world.
1535 GMT (11:35 a.m. EDT)
T-minus 20 seconds. "Go Atlas" and "Go Centaur" was just called by launch team during a final status check.
1535 GMT (11:35 a.m. EDT)
T-minus 40 seconds. Centaur's liquid oxygen and liquid hydrogen tanks are stable at flight pressures.
1535 GMT (11:35 a.m. EDT)
T-minus 1 minute. Now 60 seconds from the launch of the 55th Atlas 5 rocket.
1534 GMT (11:34 a.m. EDT)
T-minus 90 seconds. The safety system has been armed.
1534 GMT (11:34 a.m. EDT)
T-minus 1 minute, 45 seconds. Liquid oxygen and liquid hydrogen propellant topping to the Centaur upper stage is being secured.
1534 GMT (11:34 a.m. EDT)
T-minus 1 minute, 55 seconds. The launch sequencer has been commanded to start.
1534 GMT (11:34 a.m. EDT)
T-minus 2 minutes. The Atlas first stage and Centaur upper stage are now switching from ground power to internal batteries.
1533 GMT (11:33 a.m. EDT)
T-minus 2 minutes, 30 seconds. The first stage RP-1 kerosene fuel tank and the liquid oxygen have stepped up to proper flight pressure levels.
1533 GMT (11:33 a.m. EDT)
T-minus 3 minutes. The Atlas first stage liquid oxygen replenishment is being secured so the tank can be pressurized for launch.
1532 GMT (11:32 a.m. EDT)
T-minus 3 minutes, 50 seconds. The ground pyrotechnics have been enabled.
1532 GMT (11:32 a.m. EDT)
T-minus 4 minutes and counting. Clocks have resumed for the final minutes of today's countdown to launch the Atlas 5 rocket carrying GPS 2F-10. Liftoff is set to occur at 11:36 a.m. EDT.
1531 GMT (11:31 a.m. EDT)
Countdown clocks will resume in one minute.
1530 GMT (11:30 a.m. EDT)
The ULA launch director and Air Force mission director have given their permission to fly today.
1529 GMT (11:29 a.m. EDT)
Polling of the team by Atlas launch conductor has occurred. All systems are reported "go" to continue with the countdown for liftoff at 11:36 a.m. EDT.
1525 GMT (11:25 a.m. EDT)
Standing by for the launch team readiness polls.

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1523 GMT (11:23 a.m. EDT)
The Atlas 5 rocket stands 19 stories tall and weighs 737,000 pounds at launch.
1518 GMT (11:18 a.m. EDT)
No problems being reported by the launch team. Countdown continues to sit in the hold period at T-minus 4 minutes, waiting for the launch window to open at 11:36 a.m. EDT.
1511 GMT (11:11 a.m. EDT)
Here's a look at some stats about today's mission. This will be:
1509 GMT (11:09 a.m. EDT)
The GPS satellite nestled inside the nose of the Atlas 5 rocket is switching to internal power for launch.
1508 GMT (11:08 a.m. EDT)
Weather remains GO for liftoff based on the current conditions and expected to stay favorable for an 11:36 a.m. EDT launch today.
1506 GMT (11:06 a.m. EDT)
Thirty minutes from liftoff.
1502 GMT (11:02 a.m. EDT)
T-minus 4 minutes and holding. The countdown has entered the planned 30-minute hold to give the launch team a chance to review all systems and assess the weather before pressing ahead with liftoff.
1501 GMT (11:01 a.m. EDT)
T-minus 5 minutes. Standing by to go into the final built-in hold.
1456 GMT (10:56 a.m. EDT)
Now 40 minutes till launch. Rumbling away from the planet on nearly a million pounds of thrust, the Atlas 5 rocket will be flying in a basic, two-stage configuration without any added strap-on solid motors. The vehicle sports an aluminum, 14-foot-diameter nose cone that encapsulates the GPS spacecraft during the atmospheric ascent before being shed.

With the liftoff thrust not considerably more than the rocket's weight, this Atlas will display a slow and majestic rise trailing only a flickering golden flame from its RD-180 main engine.

Once above the launch pad, the rocket sets sail for the eastward trek downrange over the Atlantic Ocean, constantly gaining speed as its double-nozzle engine gulps 25,000 gallons of kerosene fuel and 50,000 gallons of superchilled liquid oxygen in just four-and-a-half minutes.

The bronze first stage, its propellants depleted and job now completed, then jettisons with the help of tiny thrusters. Some 106.5 feet long and 12.5 feet around, the stage is discarded to fall back into the open sea.

The cryogenic Centaur upper stage ignites moments after shedding the lower booster, lighting the RL10 engine to continue clawing toward orbit.

Covered with insulating foam, this stage stretches 41.5 feet in length and 10 feet in diameter. Centaur must perform two burns to loft GPS 2F-10 into the proper orbit around the planet.

1450 GMT (10:50 a.m. EDT)
The fuel-fill sequence for the first stage main engine is starting.
1446 GMT (10:46 a.m. EDT)
Atlas 5 represents the culmination of evolution stretching back several decades to America's first intercontinental ballistic missile. At the dawn of the space age, boosters named Atlas launched men into orbit during Project Mercury and became a frequent vehicle of choice to haul civil, military and commercial spacecraft to orbit.

Topped with the high-energy Centaur upper stage, Atlas rockets have been used since the 1960s to dispatch ground-breaking missions for NASA, including the Surveyors to the Moon, Mariner flights to Mars, Venus and Mercury, and the Pioneers that were the first to visit Jupiter and beyond.

In its newest era, the Atlas 5 rocket sent the Mars Reconnaissance Orbiter to the red planet in 2005, propelled the New Horizons probe toward Pluto and the solar system's outer fringes in 2006, doubled up with the dual Lunar Reconnaissance Orbiter and LCROSS impactor to the Moon in 2009, hurled Juno to Jupiter in August 2011 and dispatched the car-sized Curiosity rover on the Mars Science Lab mission in November 2013.

Today marks the 55th flight for Atlas 5, born of the Air Force's competition to develop next-generation Evolved Expendable Launch Vehicles. In its previous 54 missions since debuting in August 2002, the Atlas 5 has flown 20 flights dedicated to the Defense Department, 12 for NASA, 11 with spy satellites for the National Reconnaissance Office. and 11 commercial missions with communications and Earth-observing spacecraft.

1439 GMT (10:39 a.m. EDT)
The odds of acceptable launch weather today have improved to 80 percent.
1436 GMT (10:36 a.m. EDT)
Now 60 minutes from liftoff. Fueling of the Atlas rocket with cryogenic liquid oxygen and liquid hydrogen is complete as the countdown continues as planned for a liftoff at 11:36 a.m. EDT.
1426 GMT (10:26 a.m. EDT)
The liquid hydrogen tank in the Centaur upper stage just reached the 96 percent level. Topping is now beginning.
1423 GMT (10:23 a.m. EDT)
Fast-filling of the first stage liquid oxygen tank has been completed. Topping mode is now underway.
1415 GMT (10:15 a.m. EDT)
Centaur's liquid hydrogen tank is 30 percent full. The cryogenic propellant will be consumed with liquid oxygen by the stage's Aerojet Rocketdyne-made RL10 engine.
1414 GMT (10:14 a.m. EDT)
The first stage liquid oxygen has reached the 80 percent level.
1407 GMT (10:07 a.m. EDT)
Chilldown of the liquid hydrogen system has been accomplished. The launch team has received the "go" to begin filling the Centaur upper stage with the supercold fuel.
1406 GMT (10:06 a.m. EDT)
Launch of the Atlas 5 rocket is just 90 minutes away.

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1401 GMT (10:01 a.m. EDT)
Half of the Atlas liquid oxygen tank has been filled so far.
1354 GMT (9:54 a.m. EDT)
Upper stage liquid oxygen has reached flight level.
1353 GMT (9:53 a.m. EDT)
First stage liquid oxygen tank is 30 percent full thus far. Chilled to Minus-298 degrees F, the liquid oxygen will be used with RP-1 kerosene by the RD-180 main engine on the first stage during the initial four-and-a-half minutes of flight today. The 25,000 gallons of RP-1 were loaded into the rocket last night.
1347 GMT (9:47 a.m. EDT)
The Centaur liquid oxygen tank reached the 96 percent level. The topping off process is starting now.
1344 GMT (9:44 a.m. EDT)
The first stage liquid oxygen flow rate is switching from slow-fill to fast-fill mode.
1343 GMT (9:43 a.m. EDT)
The chilldown conditioning of liquid hydrogen propellant lines at Complex 41 is starting to prepare the plumbing for transferring the Minus-423 degree F fuel into the rocket. The Centaur holds about 12,700 gallons of the cryogenic propellant.
1342 GMT (9:42 a.m. EDT)
Now three-quarters full on Centaur liquid oxygen.
1338 GMT (9:38 a.m. EDT)
Sixty percent of the Centaur liquid oxygen tank has been filled so far.
1334 GMT (9:34 a.m. EDT)
The chilldown conditioning of the systems for the first stage liquid oxygen tank have been completed. And a "go" has been given to begin pumping supercold liquid oxygen into the Atlas 5's first stage.

The Common Core Booster stage's liquid oxygen tank is the largest tank to be filled today. It holds 49,000 gallons of cryogenic oxidizer for the RD-180 main engine.

1329 GMT (9:29 a.m. EDT)
The Centaur liquid oxygen tank has reached the 20 percent mark.
1321 GMT (9:21 a.m. EDT)
Filling of the Centaur upper stage with about 4,150 gallons of liquid oxygen has begun at Cape Canaveral's Complex 41 following the thermal conditioning of the transfer pipes.

The liquid oxygen -- chilled to Minus-298 degrees F -- will be consumed during the launch by the Centaur's single RL10 engine along with liquid hydrogen to be pumped into the stage a little later in the countdown. The Centaur will provide the thrust to put GPS 2F-10 into orbit.

1314 GMT (9:14 a.m. EDT)
The Centaur liquid oxygen pad storage area has been prepped. The next step is conditioning the transfer lines, which is now beginning to prepare the plumbing for flowing the cryogenic oxidizer.
1306 GMT (9:06 a.m. EDT)
T-minus 120 minutes and counting! The launch countdown is continuing on schedule for today's flight of the Atlas 5 rocket to deploy the GPS 2F-10 satellite.

Clocks have one more built-in hold planned at T-minus 4 minutes. During that pause the final "go" for launch will be given. All remains targeted for liftoff at 11:36 a.m. EDT from Cape Canaveral's Complex 41.

In the next couple of minutes, chilldown thermal conditioning of the mobile launch platform upon which the rocket stands will begin. This is meant to ease the shock on equipment when supercold cryogenic propellants start flowing into the rocket.

1304 GMT (9:04 a.m. EDT)
After briefing his team on procedures before entering into the final two hours of the countdown, the launch conductor at the Atlas Spaceflight Operations Center just held a pre-fueling readiness poll. All console operators reported a "ready" status.

The ULA launch director also voiced her approval for proceeding with the countdown.

Loading of cryogenic liquid oxygen and liquid hydrogen into the Atlas 5 rocket will be getting underway a short time from now.

1245 GMT (8:45 a.m. EDT)
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1236 GMT (8:36 a.m. EDT)
T-minus 2 hours and holding. The countdown has just entered the first of two planned holds over the course of the day that will lead to the 11:36 a.m. EDT launch of the Atlas rocket. The holds give the team some margin in the countdown timeline to deal with technical issues or any work that is running behind. The final hold is scheduled to occur at T-minus 4 minutes.
1015 GMT (6:15 a.m. EDT)
The early portion of the countdown has been going smoothly. There are no issues being reported in the count and activities are on schedule.
0915 GMT (5:15 a.m. EDT)
In today's first weather briefing to mission managers, all current conditions are observed GO for launch of the Atlas 5 rocket and odds for the launch window stand at 70 percent favorable. The main concern that meteorologists are watching are cumulus and anvil clouds.

The outlook predicts scattered clouds at 2,500 and a broken deck at 25,000 feet, isolated showers, good visibility, southwesterly winds of 12 gusting to 16 knots, a temperature in the high 80s F.

The Atlas-Centaur rocket has been powered up at Complex 41 and guidance system testing is getting started for today's launch, as the countdown progresses as planned.

0845 GMT (4:45 a.m. EDT)
The countdown is beginning for today’s launch of the Atlas 5 rocket to haul the Air Force’s GPS 2F-10 navigation satellite into orbit.

Clocks are picking up the seven-hour sequence of work that will prepare the booster, payload and ground systems for blastoff at 11:36 a.m. EDT (1536 GMT).

The launch team will begin powering up the rocket to commence standard pre-flight tests. Over the subsequent few hours, final preps for the Centaur's liquid oxygen and liquid hydrogen systems will be performed, along with a test of the rocket's guidance system and the first stage propulsion and hydraulic preps, internal battery checks and testing of the GPS metric tracking system used to follow the rocket as it flies downrange, plus a test of the S-band telemetry relay system.

A planned hold begins when the count reaches T-minus 120 minutes. Near the end of the hold, the team will be polled to verify all is in readiness to start fueling the rocket for launch.

Supercold liquid oxygen begins flowing into the Centaur upper stage, followed by the first stage filling. Liquid hydrogen fuel loading for Centaur will be completed a short time later.

A final hold is scheduled at the T-minus 4 minute mark. That pause will give everyone a chance to finish any late work and assess the status of the rocket, payload, Range and weather before proceeding into the last moments of the countdown.

The launch window extends 18 minutes to 11:54 a.m. EDT (1554 GMT).

TUESDAY, JULY 14, 2015
After a record-setting 21 days from the start of stacking to rollout from the assembly building, United Launch Alliance Atlas 5 rocket was on the move this morning for Wednesday's flight to place a Global Positioning System spacecraft into orbit.

Liftoff of the GPS 2F-10 satellite is slated for 11:36 a.m. EDT at the opening of an 18-minute window.

"It will add further capabilities to the most-widely recognized satellite constellation in the world," said Col. Alvin Burse, GPS 2F-10 mission director.

Besting the previous mark of 25 days from commencing stacking to rollout, this whirlwind launch campaign saw the rocket and its payload integrated in just three weeks. It is part of "span reductions" initiative that heighten efficiencies, increase available slots in the manifest and cut costs.

"As our vehicle matures, we're continuing to streamline and consolidate processes where it makes sense," said Laura Maginnis, United Launch Alliance's mission management deputy director.

"We are working to keep our processes lean and efficient, and the shorter span time does allow us to have more manifest flexibility."

The United Launch Alliance booster was wheeled out aboard a mobile platform, emerging from the assembly building where the rocket's two stages and the payload were integrated over the past 21 days.

The slow drive from the 30-story Vertical Integration Facility to the launch pad, which began at 9:55 a.m., used a pair of specially-made “trackmobiles” to carry the rocket's 1.4-million pound mobile launching platform along rail tracks for the 1,800-foot trip. The 19-story-tall satellite booster will launch the GPS craft directly into the navigation constellation. Deployment of the satellite occurs 3 hours and 23 minutes into flight.

The rocket is flying the 401 vehicle configuration. The version features two stages and a four-meter-diameter nose cone. It is powered off the launch pad by an RD AMROSS RD-180 main engine. The Centaur upper stage is equipped with an Aerojet Rocketdyne RL10C-1.

Countdown clocks begin ticking early Wednesday seven hours before launch, leading to activation of the rocket, final testing and system preps.

There is a 70 percent chance of acceptable weather.

"We are methodically preparing for this GPS 2F Launch on the Atlas 5. The GPS 2F satellites increase GPS signal capabilities, increase user accuracy with more accurate space atomic clocks, and reduces overall constellation risk," said Lt. Gen. Samuel Greaves, Space and Missile Systems Center commander.

SUNDAY, JULY 12, 2015
PREVIEW: The Global Positioning System, its precision navigation and timing services made possible by the U.S. Air Force and provided free-of-charge to the planet’s civilian population, is a marvel of the modern world, and the orbiting network will receive a fresh satellite Wednesday.

The $245 million GPS 2F-10 satellite is scheduled for liftoff from Cape Canaveral aboard a United Launch Alliance Atlas 5 rocket during an available launch opportunity that extends 18 minutes from 11:36 to 11:54 a.m. EDT.

Weather forecasters are predicting a 70 percent chance of meeting the launch rules.

Read our full story.