Completing an October to remember, the third Atlas 5 rocket launch in just 29 days thundered into space today, this time to replace an aging satellite in the Global Positioning System.

Read our launch story.

1958 GMT (3:58 p.m. EDT)
“Congratulations to the entire team on today’s successful launch of the GPS 2F-11 satellite! Today’s launch was made possible by the exceptional performance and teamwork exhibited by the entire team, including the men and women of ULA, our many mission partners, and our U.S. Air Force customer,” said Jim Sponnick, ULA vice president, Atlas and Delta Programs.

“GPS is omnipresent in our everyday lives and the system provides a critical service to the all of those serving in our military around the world. All of the operational GPS satellites have been launched on Atlas and Delta rockets and the U.S. Air Force does an outstanding job of operating this essential system.”

1942 GMT (3:42 p.m. EDT)
The next Atlas 5 rocket launch from Cape Canaveral is planned for Dec. 3, around 5:55 p.m. EST (2255 GMT) on a commercial cargo run to the International Space Station.
1940 GMT (3:40 p.m. EDT)
This was the 130th successful Atlas program launch in a row spanning more than two decades and the 59th for an Atlas 5.
1936 GMT (3:36 p.m. EDT)
T+plus 3 hours, 23 minutes. SPACECRAFT SEPARATION! The Centaur upper stage has deployed the Global Positioning System 2F-11 satellite for the U.S. Air Force.
1933 GMT (3:33 p.m. EDT)
T+plus 3 hours, 20 minutes. The second burn by Centaur inserted the rocket into another precise orbit as targeted. The vehicle is in a circular orbit of approximately 11,000 nautical miles at 55 degrees inclination.
1931 GMT (3:31 p.m. EDT)
T+plus 3 hours, 18 minutes. MECO 2. Centaur has completed its second burn of the day. It was a planned 87-second firing to circularize the orbit.
1930 GMT (3:30 p.m. EDT)
T+plus 3 hours, 17 minutes. Ignition! The Centaur's single RL10C engine has re-ignited to finish the climb to the GPS constellation.
1929 GMT (3:29 p.m. EDT)
T+plus 3 hours, 16 minutes. Centaur pressurization sequence complete. Liquid hydrogen and liquid oxygen system prestarts now underway.
1925 GMT (3:25 p.m. EDT)
T+plus 3 hours, 12 minutes. Five minutes away from the burn. Centaur is reorienting to the proper position for the next engine firing.
1813 GMT (2:13 p.m. EDT)
T+plus 2 hours. All parameters from the Centaur are reported normal as the coast continues.
1730 GMT (1:30 p.m. EDT)
VIDEO REPLAY of today's Atlas 5 rocket launch with the GPS 2F-11.
1713 GMT (1:13 p.m. EDT)
T+plus 1 hour. The vehicle is coasting above the Indian Ocean and heading away from the Earth in this preliminary orbit.
1635 GMT (12:35 p.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-11 satellite to complete today's mission.
1633 GMT (12:33 p.m. EDT)
Good performance from the vehicle has resulted in a nominal transfer orbit being achieved.
1630 GMT (12:30 p.m. EDT)
T+plus 17 minutes, 10 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.
1629 GMT (12:29 p.m. EDT)
T+plus 16 minutes, 10 seconds. Everything looking normal with one minute to go in this burn.
1628 GMT (12:28 p.m. EDT)
T+plus 15 minutes, 30 seconds. RL10 engine parameters still look good.
1627 GMT (12:27 p.m. EDT)
T+plus 14 minutes, 20 seconds. Now orbital. The rocket traveling over 17,647 mph.
1626 GMT (12:26 p.m. EDT)
T+plus 13 minutes. Centaur remains on course and looking good.
1625 GMT (12:25 p.m. EDT)
T+plus 12 minutes, 15 seconds. About five minutes are left in this burn of Centaur.
1623 GMT (12:23 p.m. EDT)
T+plus 10 minutes. All systems reported stable as the Centaur fires to reach an initial Earth orbit.
1622 GMT (12:22 p.m. EDT)
T+plus 9 minutes. Centaur performance is reported right on target.
1620 GMT (12:20 p.m. EDT)
T+plus 7 minutes. The rocket is tracking right down the planned flight path.
1618 GMT (12:18 p.m. EDT)
T+plus 5 minutes. Centaur engine readings look good as this burn gets underway.
1617 GMT (12:17 p.m. EDT)
T+plus 4 minutes, 35 seconds. The two halves of the four-meter-diameter Atlas 5 rocket nose cone encapsulating the spacecraft have separated.
1617 GMT (12:17 p.m. EDT)
T+plus 4 minutes, 24 seconds. Centaur has ignited! The RL10C-1 engine is up and running at full thrust to power the vehicle into orbit.
1617 GMT (12:17 p.m. EDT)
T+plus 4 minutes, 12 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.
1617 GMT (12:17 p.m. EDT)
T+plus 4 minutes, 7 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.
1616 GMT (12:16 p.m. EDT)
T+plus 3 minutes, 45 seconds. Atlas now weighs just a quarter of what it did at liftoff.
1615 GMT (12:15 p.m. EDT)
T+plus 2 minutes, 45 seconds. Reaction control system has been activated.
1615 GMT (12:15 p.m. EDT)
T+plus 2 minutes, 35 seconds. Atlas continues tracking on course.
1615 GMT (12:15 p.m. EDT)
T+plus 2 minutes, 30 seconds. Atlas now weighs half of what it did at liftoff.
1615 GMT (12:15 p.m. EDT)
T+plus 2 minutes, 15 seconds. Vehicle systems looking good.
1614 GMT (12:14 p.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.
1614 GMT (12:14 p.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.
1614 GMT (12:14 p.m. EDT)
T+plus 85 seconds. All looks good aboard Atlas as it passes Mach 1.
1614 GMT (12:14 p.m. EDT)
T+plus 60 seconds. One minute into the ascent of GPS 2F-11.
1613 GMT (12:13 p.m. EDT)
T+plus 40 seconds. The Atlas 5 is sending a thunderous roar across Florida's spaceport. Good engine performance reported.
1613 GMT (12:13 p.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.
1613 GMT (12:13 p.m. EDT)
LIFTOFF! Liftoff of the Atlas 5 rocket with a new Global Positioning System satellite, connecting man with the practical benefits of space.
1612 GMT (12:12 p.m. EDT)
T-minus 20 seconds. "Go Atlas" and "Go Centaur" was just called by launch team during a final status check.
1612 GMT (12:12 p.m. EDT)
T-minus 40 seconds. Centaur's liquid oxygen and liquid hydrogen tanks are stable at flight pressures.
1612 GMT (12:12 p.m. EDT)
T-minus 1 minute. Now 60 seconds from the launch of the 59th Atlas 5 rocket and 11th Block 2F GPS satellite.
1611 GMT (12:11 p.m. EDT)
T-minus 90 seconds. The safety system has been armed.
1611 GMT (12:11 p.m. EDT)
T-minus 1 minute, 45 seconds. Liquid oxygen and liquid hydrogen propellant topping to the Centaur upper stage is being secured.
1611 GMT (12:11 p.m. EDT)
T-minus 1 minute, 55 seconds. The launch sequencer has been commanded to start.
1611 GMT (12:11 p.m. EDT)
T-minus 2 minutes. The Atlas first stage and Centaur upper stage are now switching from ground power to internal batteries.
1610 GMT (12:10 p.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.
1610 GMT (12:10 p.m. EDT)
T-minus 3 minutes. The Atlas first stage liquid oxygen replenishment is being secured so the tank can be pressurized for launch.
1609 GMT (12:09 p.m. EDT)
T-minus 3 minutes, 50 seconds. The ground pyrotechnics have been enabled.
1609 GMT (12:09 p.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-11.
1608 GMT (12:08 p.m. EDT)
Countdown clocks will resume in one minute.
1607 GMT (12:07 p.m. EDT)
The ULA launch director and Air Force mission director have given their permission to fly today.
1606 GMT (12:06 p.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 12:13 p.m. EDT.
1604 GMT (12:04 p.m. EDT)
Standing by for the launch team readiness polls.

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1559 GMT (11:59 a.m. EDT)
The Atlas 5 rocket stands 189 feet tall and weighs 737,000 pounds at launch.
1555 GMT (11:55 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 12:13 p.m. EDT.
1550 GMT (11:50 a.m. EDT)
Here's a look at some stats about today's mission. This will be:
1548 GMT (11:48 a.m. EDT)
The GPS satellite nestled inside the nose of the Atlas 5 rocket is switching to internal power for launch.
1546 GMT (11:46 a.m. EDT)
Weather remains GO for liftoff based on the current conditions and expected to stay favorable for an 12:13 p.m. EDT launch today.
1543 GMT (11:43 a.m. EDT)
Thirty minutes from liftoff. This will be the 71st GPS satellite launch since 1978, the 16th to use an Atlas rocket and the fifth Block 2F on Atlas 5.
1539 GMT (11:39 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.
1538 GMT (11:38 a.m. EDT)
T-minus 5 minutes. Standing by to go into the final built-in hold.
1533 GMT (11:33 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 trek 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-11 into the proper orbit around the planet.

1527 GMT (11:27 a.m. EDT)
The fuel-fill sequence for the first stage main engine is starting.
1523 GMT (11:23 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 59th flight for Atlas 5, born of the Air Force's competition to develop next-generation Evolved Expendable Launch Vehicles. In its previous 58 missions since debuting in August 2002, the Atlas 5 has flown 22 flights dedicated to the Defense Department, 12 for NASA, 12 with spy satellites for the National Reconnaissance Office and 12 commercial missions with communications and Earth-observing spacecraft.

1513 GMT (11:13 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 12:13 p.m. EDT.
1505 GMT (11:05 a.m. EDT)
The liquid hydrogen tank in the Centaur upper stage just reached the 96 percent level. Topping is now beginning.
1503 GMT (11:03 a.m. EDT)
Fast-filling of the first stage liquid oxygen tank has been completed. Topping mode is now underway.
1455 GMT (10:55 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.
1454 GMT (10:54 a.m. EDT)
The first stage liquid oxygen has reached the 80 percent level.
1446 GMT (10:46 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.
1443 GMT (10:43 a.m. EDT)
Launch of the Atlas 5 rocket is just 90 minutes away.

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1441 GMT (10:41 a.m. EDT)
Half of the Atlas liquid oxygen tank has been filled so far.
1434 GMT (10:34 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 minutes of flight today. The 25,000 gallons of RP-1 were loaded into the rocket last night.
1433 GMT (10:33 a.m. EDT)
Upper stage liquid oxygen has reached flight level.
1430 GMT (10:30 a.m. EDT)
The Centaur liquid oxygen tank reached the 96 percent level. The topping off process is starting now.
1424 GMT (10:24 a.m. EDT)
The first stage liquid oxygen flow rate is switching from slow-fill to fast-fill mode.
1423 GMT (10:23 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.
1422 GMT (10:22 a.m. EDT)
Now three-quarters full on Centaur liquid oxygen.
1418 GMT (10:18 a.m. EDT)
Sixty percent of the Centaur liquid oxygen tank has been filled so far.
1412 GMT (10:12 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.

1410 GMT (10:10 a.m. EDT)
Learn more about the process United Launch Alliance uses to fuel Atlas 5 rockets.
1409 GMT (10:09 a.m. EDT)
The Centaur liquid oxygen tank has reached the 20 percent mark.
1401 GMT (10:01 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-11 into orbit.

1352 GMT (9:52 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.
1343 GMT (9:43 a.m. EDT)
T-minus 2 hours and counting! The launch countdown is continuing on schedule for today's flight of the Atlas 5 rocket to deploy the GPS 2F-11 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 12:13 p.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.

1341 GMT (9:41 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 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.

1333 GMT (9:33 a.m. EDT)
Man stations for cryogenic tanking. That's the word to the launch team.
1320 GMT (9:20 a.m. EDT)
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1313 GMT (9:13 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 12:13 p.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.
1258 GMT (8:58 a.m. EDT)
Crews are departing the launch pad following completion of all hands-on work this morning.
1220 GMT (8:20 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.
0950 GMT (5:50 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 90 percent favorable. The main concern that meteorologists are watching are cumulus clouds.

The outlook predicts a few clouds at 3,000 feet, scattered clouds at 24,000 feet, good visibility, easterly winds of 10 gusting to 16 knots and a temperature of 80 degrees 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.

0900 GMT (5:00 a.m. EDT)
The countdown is beginning for today’s launch of the Atlas 5 rocket to haul the Air Force’s GPS 2F-11 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 12:13 p.m. EDT (1613 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 19 minutes to 12:32 p.m. EDT (1632 GMT).

With a leaky launch pad valve removed and replaced, preparations are back on track for the United Launch Alliance Atlas 5 rocket and GPS 2F-11 navigation satellite for liftoff on Saturday.

The valve in question was misbehaving on Thursday, forcing the launch to be delayed 24 hours so technicians could fix the issue. It is part of the pad's critical water suppression system.

"The valve was replaced and verification tests were successfully completed," ULA said in a statement Friday afternoon.

Saturday's launch window is 12:13 to 12:32 p.m. EDT (1613-1632 GMT).

Weather forecasters continue to predict a 90 percent chance of favorable launch conditions.

"On launch day, high pressure is well established across the Space Coast giving way to partly cloudy skies during the count. Winds will be easterly 13-17 knots during the count and at T-0. The primary concern for launch is cumulus clouds forming in the onshore easterly flow," Air Force meteorologists say.

DELAY. Friday's flight of the United Launch Alliance Atlas 5 rocket has been pushed back to Saturday at Cape Canaveral Air Force Station in Florida.

Officials made the call on Thursday evening to postpone the launch 24 hours to correct a leak discovered in a ground support equipment valve for the launch pad water suppression system. The valve will require repair or replacement.

The 19-minute launch window on Saturday extends from 12:13 to 12:32 p.m. EDT (1613-1632 GMT).

The rocket was rolled to Complex 41's pad at 11:00 a.m. EDT on Friday to begin final preparations. The countdown starts seven hours before liftoff time.

Weather forecasters predict a 90 percent chance of acceptable conditions on Saturday.

The rocket will place the Global Positioning System 2F-11 navigation satellite into orbit.

Continuing to shorten the time from the start of stacking to rollout from the assembly building, United Launch Alliance has readied its next Atlas 5 rocket and moved it to the pad this morning for Friday's flight to place a Global Positioning System spacecraft into orbit.

Liftoff of the GPS 2F-11 satellite is slated for 12:17 p.m. EDT at the opening of a 19-minute window.

Besting the previous mark of 21 days from commencing stacking to rollout, and 25 days before that, this whirlwind launch campaign saw the rocket and its payload integrated in just 17 days. It is part of "span reductions" initiative that heighten efficiencies, increase available slots in the manifest and cut costs.

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 two weeks.

The slow drive from the 30-story Vertical Integration Facility to the launch pad, which began at 11:00 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 GPS 2F satellites play a key role in our modernization effort to provide new space-based capabilities for users around the globe and for decades to come,” said Lt. Gen. Samuel Greaves, SMC commander and Air Force Program Executive Officer for Space.

“We have successfully placed into operation 10 in a series of 12 procured Boeing-built space vehicles, and thanks to the exceptional team of government, industry and launch personnel we are poised to launch the 11th GPS 2F satellite aboard an Atlas 5 401 launch vehicle later this week.”

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 seven hours before launch, leading to activation of the rocket, final testing and system preps.

There is a 90 percent chance of acceptable weather.

PREVIEW: The penultimate satellite in the current generation of Global Positioning System spacecraft will be deployed Friday, capping a hectic four weeks with three launches from two coasts for the Atlas 5 rocket fleet.

Read our full story.