After 14 months in space and more than 450 maneuvers, the first satellite in the U.S. military's next-generation secure communications network now expects to complete its arduous journey to reach the correct orbit by late October and enter service in March.

A manufacturing mishap prevented the Advanced Extremely High Frequency satellite's main propulsion system from firing once the craft reached space, prompting ground controllers to devise emergency plans for salvaging the mission.

Burning its exotic electric thrusters for the past year, AEHF 1 has reached an orbit of 24,000 by 22,300 miles. It should achieve the desired circular orbit with a 4.8-degree inclination by month's end, allowing payload activation and testing to occur through February in preparation for entering service at long last in March.

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As investigators narrow the list of potential culprits in the Advanced Extremely High Frequency satellite's main propulsion system problem, the Air Force has decided to delay launching the follow-up spacecraft and rearrange its upcoming Atlas rocket manifest.

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Moving into the next phase of its orbital rescue, the Air Force's Advanced Extremely High Frequency satellite is warming up exotic electric thrusters to begin 10 months of propulsion-with-persistence that's needed to save the craft's life.

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The U.S. Air Force has completed the initial phase of its multi-step, multi-month strategy to maneuver the new secure communications satellite into the proper orbit without the main engine operating.

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As tiny thrusters continue to nudge the U.S. military's AEHF 1 satellite toward a higher orbit, investigators hope to know within the next few weeks what knocked out the craft's main engine and whether the program's next launch will be delayed.

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A rescue plan is being implemented to salvage the U.S. military's pricy new communications satellite despite a serious malfunction that knocked out its main engine and stymied the craft's maneuvering ability.

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Our gallery of launch photos taken at the Kennedy Space Center Press Site is posted here.

A sophisticated satellite was launched into space today to improve the preeminent path of communications between the president, military commanders and troops on the battlefield, ensuring a survivable line of contact even in hellish scenarios of nuclear warfare.

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"Our number one priority is delivering mission success for our customer," said Mike Davis, Lockheed Martin's AEHF vice president. "The AEHF system will vastly improve battlefield communications, delivering secure, real-time, connectivity to a greater number of forces in the field, and their commanders anywhere on the globe. We look forward to successfully executing the next steps necessary to making this national asset operational for the warfighter."

"We are proud to be part of the U.S. Air Force and Lockheed Martin team that has worked so hard to launch this capability vital to our warfighters," said Stuart Linsky, vice president, Protected SatCom Programs, for Northrop Grumman's Aerospace Systems sector.

"This morning's successful launch is testimony to the dedication, skill and operational excellence of the entire government-industry AEHF team," said Col. Michael Sarchet, commander of the Protected Satellite Communications Group at the Air Force's Space and Missile Systems Center.

"For over 15 years, the Milstar constellation has served as the backbone of secure military communications, helping the military operate in a secure mode without concern of enemy interference. AEHF will significantly enhance our national security space architecture, and we eagerly anticipate providing this new capability to the warfighter."

Ground controllers are communicating with the AEHF 1 spacecraft and all systems are reported in good shape following the satellite's successful trip into orbit.

The next Atlas launch is scheduled for September 20 from Vandenberg Air Force Base in California. That flight will deploy a classified spy satellite payload for the National Reconnaissance Office.

"ULA is proud to have played an important role in the successful launch of the first of three AEHF satellites for this critical constellation that will directly support the warfighter on the battlefield," said Jim Sponnick, United Launch Alliance's vice president for Mission Operations.

"This was a tremendous launch campaign highlighted by close teamwork between the U.S. Air Force, the ULA launch team and our many mission partners that made today's successful launch possible. We look forward to launching AEHF 2 in 2011."

T+plus 51 minutes, 6 seconds. SPACECRAFT SEPARATION! The Centaur upper stage has deployed the first Advanced Extremely High Frequency satellite into orbit following today's launch from Cape Canaveral.

T+plus 50 minutes. One minute away from releasing the payload.

T+plus 48 minutes, 25 seconds. The thermal roll has been nulled out.

T+plus 47 minutes, 50 seconds. The vehicle is more than 2,900 miles in altitude.

T+plus 41 minutes. Deployment of the AEHF 1 spacecraft to complete today's launch sequence is expected at 7:58 a.m. EDT.

T+plus 40 minutes. Centaur is operating well with good battery voltages and tank pressures. Telemetry from the rocket is being routed back to the Cape via NASA's Tracking and Data Relay Satellite System.

T+plus 39 minutes, 20 seconds. The vehicle is soaring above the Indian Ocean as it climbs away from the planet. Currently 1,400 miles in altitude.

T+plus 36 minutes, 30 seconds. The upper stage continues in its thermal conditioning roll while quietly coasting in the parking orbit.

T+plus 34 minutes. The Centaur's orbit is much higher than originally advertised in press materials. The supergeosynchronous transfer orbit stretches from 138 statute miles at its lowest point to over 31,200 statute miles at its highest and inclined 22.2 degrees to the equator.

T+plus 31 minutes. Centaur has turned itself to the proper orientation for releasing the payload.

T+plus 29 minutes. Although the Centaur has finished firing, the rocket won't immediately deploy the payload. That milestone moment will wait about 23 minutes as the rocket crosses Africa and Madagascar, eventually flying within communications range of the Diego Garcia tracking station on an island in the Indian Ocean.

"As part of the mission success process that Lockheed Martin and the MILSATCOM folks are working to, they need to have assured telemetry coverage of that critical separation event. That will also enable us to get links for video, to have a forward-facing video view of the spacecraft separation," said Bob Winn, the ULA mission manager.

Release of the payload from the rocket to complete the launch is expected at T+plus 51 minutes.

T+plus 27 minutes, 43 seconds. MECO 2. Main engine cutoff confirmed. Centaur has completed its second burn of the morning.

T+plus 26 minutes, 30 seconds. Centaur is over 6,100 miles downrange from the launch pad, traveling at 21,635 mph.

T+plus 25 minutes, 45 seconds. About two minutes are left in the burn to reach the planned geosynchronous transfer orbit.

T+plus 24 minutes, 30 seconds. The engine is burning well. This is a planned five-and-a-half-minute firing by the Centaur's single Pratt & Whitney Rocketdyne RL10 engine.

T+plus 23 minutes, 25 seconds. Bus and battery voltages, tank pressures and other system measurements look good.

T+plus 23 minutes, 10 seconds. Vehicle acceleration is smooth at 0.65 g's.

T+plus 22 minutes, 24 seconds. Ignition and full thrust! The Centaur's single RL10 engine has re-ignited to accelerate the AEHF payload into the planned deployment orbit.

T+plus 22 minutes. Centaur is getting pressurized again in preparation for the next engine burn.

T+plus 19 minutes. The flight path is taking the vehicle over the equatorial Atlantic Ocean, just off the western coast of Africa.

T+plus 18 minutes, 30 seconds. Centaur's onboard systems are stable in this coast period continues.

T+plus 18 minutes. That first burn by Centaur inserted the rocket into an orbit with a high point of 796 statute miles, a low point of 104 statute miles and inclination of 27.66 degrees.

T+plus 16 minutes, 40 seconds. All vehicle parameters still reported normal.

T+plus 15 minutes, 30 seconds. The rocket is performing its turn to the proper position for the next engine firing.

T+plus 14 minutes, 11 seconds. MECO 1. Centaur's main engine has shut down following its first burn today, achieving a preliminary orbit around Earth. The rocket will coast in this orbit for about 8 minutes before the RL10 engine re-ignites.

T+plus 13 minutes, 45 seconds. Centaur systems remain in good shape as the rocket nears orbit.

T+plus 13 minutes, 15 seconds. Everything looking normal with one minute to go in this burn.

T+plus 12 minutes, 45 seconds. Centaur remains on course and looking good. The vehicle is speeding along at 16,825 mph.

T+plus 11 minutes, 20 seconds. RL10 engine parameters still look good.

T+plus 10 minutes, 15 seconds. About four minutes are left in this burn of Centaur.

T+plus 9 minutes, 40 seconds. The rocket is 171 miles in altitude, some 1,452 miles downrange and traveling at 14,751 mph.

T+plus 9 minutes. The RL10 continues to perform well, burning liquid hydrogen and liquid oxygen propellants.

T+plus 8 minutes. All systems reported stable as the Centaur fires to reach an initial Earth orbit.

T+plus 7 minutes, 15 seconds. Centaur is 161 miles in altitude, 915 miles downrange from the launch pad, traveling at 13,543 mph.

T+plus 6 minutes, 55 seconds. The rocket is performing a planned roll to improve the link with NASA's orbiting Tracking and Data Relay Satellite System.

T+plus 6 minutes, 5 seconds. The rocket is tracking right down the planned flight path.

T+plus 5 minutes, 15 seconds. Now 125 miles in altitude, 490 miles downrange from the launch pad, traveling at 12,789 mph.

T+plus 5 minutes, 5 seconds. Centaur engine readings look good as this burn gets underway.

T+plus 4 minutes, 37 seconds. Centaur has ignited! The RL10 engine is up and running at full thrust for its first of two planned firings today.

T+plus 4 minutes, 29 seconds. The Atlas 5's Common Core Booster first stage has been jettisoned, and the Centaur upper stage's liquid hydrogen and liquid oxygen systems are being readied for engine start.

T+plus 4 minutes, 19 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.

T+plus 3 minutes, 40 seconds. The two-halves of the Atlas 5 rocket nose cone encapsulating the AEHF 1 spacecraft have separated, exposed the satellite to space. Also jettisoned was the Forward Load Reactor, a two-piece deck that rings the Centaur stage to support the bulbous fairing during launch.

T+plus 3 minutes, 15 seconds. The RD-180 main engine continues to fire normally, burning a mixture of highly refined kerosene and liquid oxygen.

T+plus 3 minutes. The rocket is 55 miles in altitude, some 99 miles downrange and traveling at 6,025 mph.

T+plus 2 minutes, 45 seconds. Reaction control system has been activated.

T+plus 2 minutes, 3 seconds. Boosters one, two and then three have jettisoned. The Aerojet-made solid rocket motors have successfully separated from the Atlas 5, having completed their job of adding a powerful kick at liftoff.

T+plus 94 seconds. Solid rocket booster burnout has occurred. But the spent motors will remain attached to the first stage for about 23 seconds, until the Atlas 5 reaches a point where the airborne dynamic pressure reduces to an allowable level for a safe jettison.

T+plus 1 minute, 10 seconds. The RD-180 has revved back to full throttle.

T+plus 60 seconds. The launcher is departing Cape Canaveral to give the first Advanced Extremely High Frequency communications satellite a 51-minute ride to orbit.

T+plus 45 seconds. Mach 1.

T+plus 40 seconds. The main engine is throttling down to 76 percent of rated thrust to ease the stresses on the vehicle in the lower atmosphere.

T+plus 15 seconds. Pitch, yaw and roll maneuvers are underway as the Atlas 5 lights up the early morning sky with its RD-180 engine and three solid rocket boosters.

LIFTOFF! Liftoff of the Atlas 5 rocket and AEHF 1, advancing the satellite technology in the military's preeminent line of communications.

T-minus 20 seconds. "Go Atlas" and "Go Centaur" was just called by launch team during a final status check.

T-minus 40 seconds. Centaur's liquid oxygen and liquid hydrogen tanks are stable at flight pressures.

T-minus 1 minute. Now 60 seconds left in what has been a very smooth countdown this morning.

T-minus 90 seconds. The safety system has been armed.

T-minus 1 minute, 50 seconds. Liquid oxygen and liquid hydrogen propellant topping to the Centaur upper stage is being secured.

T-minus 1 minute, 55 seconds. The launch sequencer has been commanded to start.

T-minus 2 minutes. The Atlas first stage and Centaur upper stage are now switching from ground power to internal batteries.

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.

T-minus 3 minutes. The Atlas first stage liquid oxygen replenishment is being secured so the tank can be pressurized for launch.

T-minus 3 minutes, 50 seconds. The ground pyrotechnics have been enabled.

T-minus 4 minutes and counting. Clocks have resumed for the final minutes of today's countdown to launch the Atlas 5 rocket carrying the Advanced Extremely High Frequency 1 spacecraft. Liftoff is set to occur at 7:07 a.m. EDT.

Countdown clocks will resume in one minute.

The ULA launch director and the Air Force mission director have given their "go" for today's on-time liftoff.

Polling of the team by Atlas launch conductor just occurred. All systems are reported "go" to continue with the countdown for liftoff at 7:07 a.m. EDT.

Here's a look at some stats about today's mission. This will be:

• The 604th launch for Atlas program since 1957
• The 318th Atlas to occur from Cape Canaveral
• The 22nd launch of an Atlas 5 since 2002
• The 20th Atlas 5 to occur from the Cape
• The 14th Atlas 5 under United Launch Alliance
• The 1st Atlas 5 to fly in the 531 configuration
• The 9th Department of Defense launch of Atlas 5
• The 3rd Atlas launch of 2010

T-minus 4 minutes and holding. The countdown has entered the planned 10-minute hold to give the launch team a chance to review all systems before pressing ahead with liftoff.

The first stage liquid oxygen tank and Centaur's liquid oxygen and liquid hydrogen tanks are reported at flight level.

T-minus 5 minutes. Standing by to go into the final built-in hold.

The AEHF 1 satellite nestled inside the nose cone of the Atlas 5 rocket is switching to internal power for launch.

There are no weather constraints this morning and conditions are perfect for liftoff 20 minutes from now.

The fuel-fill sequence for the first stage main engine is starting.

Thirty minutes from liftoff. The countdown clocks are heading to the T-minus 4 minute mark where a planned 10-minute hold will occur. Launch of Atlas 5 remains scheduled for 7:07 a.m. EDT.

The first rays of sunrise beginning to come over the horizon on a beautiful Florida morning here.

Live video of the Atlas launch is streaming on this page. Hit reload for the video to activate.

Fast-filling of the first stage liquid oxygen tank has been completed. Topping mode is now underway.

The liquid hydrogen tank in the Centaur upper stage just reached the 97 percent level. Topping is now beginning.

Now 55 minutes from liftoff. Fueling of the Atlas rocket with cryogenic liquid oxygen and liquid hydrogen is proceeding as planned for a liftoff at 7:07 a.m. EDT.

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Centaur's liquid hydrogen tank is 50 percent full. The cryogenic propellant will be consumed with liquid oxygen by the stage's Pratt & Whitney Rocketdyne-made RL10 engine.

The first stage liquid oxygen tank is 80 percent full now.

The first stage liquid oxygen has reached the 70 percent level.

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.

First stage liquid oxygen tank is 40 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-quarter minutes of flight today. The 25,000 gallons of RP-1 were loaded into the rocket earlier.

The Centaur engine chilldown sequence is being initiated.

Upper stage liquid oxygen has reached flight level.

Now just 90 minutes away from launch. The Atlas 5 stands bathed in powerful spotlights at Complex 41, being fueled up for liftoff. There are no reports of any issues and the weather looks good.

The Centaur liquid oxygen tank reached the 95 percent level. The topping off process is starting now.

The first stage liquid oxygen loading is switching from slow-fill to fast-fill mode.

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 12,680 gallons of the cryogenic propellant.

Centaur liquid oxygen is three-quarters full.

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 48,860 gallons of cryogenic oxidizer for the RD-180 main engine.

The Centaur liquid oxygen tank has reached the 30 percent mark.

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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 perform two firings to propel the payload into geosynchronous transfer orbit.

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.

T-minus 120 minutes and counting! The launch countdown is continuing on schedule for today's flight of the Atlas 5 rocket with the first Advanced EHF communications satellite aboard.

Clocks have one more built-in hold planned at T-minus 4 minutes. That pause will last 10 minutes during which time the final "go" for launch will be given. All remains targeted for liftoff at 7:07 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.

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 and Air Force mission director also voiced their 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.

T-minus 2 hours and holding. The countdown has just entered the first of two planned holds over the course of the morning that will lead to the 7:07 a.m. EDT launch of the Atlas rocket. This initial pause lasts 30 minutes, giving 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 and will last for 10 minutes.

The Complex 41 pad and the blast danger area have been cleared of all workers for the remainder of the countdown.

Good day from the Florida spaceport where clocks are counting down to the 7:07 a.m. EDT liftoff of the Atlas 5 rocket. The team just completed guidance system testing and the pad crew's final hands-on work is wrapping up.

The weather outlook for this morning's two-hour launch window remains 80 percent favorable. Air Force meteorologists are calling for a chance of isolated showers, scattered low- and high-level clouds, good visibility, westerly winds of 8 to 12 knots and a temperature of 81 degrees.

Cumulus clouds and anvil clouds are the two potential threats to violating the launch weather rules.

The countdown clocks are starting to tick for today's launch of the AEHF 1 spacecraft aboard the Atlas 5 vehicle. The next seven hours of work will prepare the rocket, payload and ground systems for the upcoming sunrise blastoff.

We will provide live play-by-play coverage of flight beginning around 4 a.m. EDT.

Officials are pressing ahead with Saturday morning's launch of the Atlas 5 rocket as scheduled. The launch team will begin manning their stations in a little while to start the countdown at 12:07 a.m. EDT.

Liftoff remains targeted for 7:07 a.m. EDT from Cape Canaveral, Florida.

An issue with the Eastern Range is being worked tonight, bringing into question whether the Atlas 5 rocket will be permitted to launch Saturday morning as scheduled. Officials say a "go" or "no go" decision should come by 10:30 p.m. EDT. Check back for further information.

Saturday's launch of the Atlas 5 rocket will be the first flight of the vehicle's 531 configuration, which is distinguished by the combination of a five-meter payload fairing, three solid rocket boosters and a single-engine Centaur upper stage.

Depending on a payload's weight and desired orbit, mission planners add strap-on solid boosters to the United Launch Alliance-made rocket to incrementally increase the vehicle's performance.

Atlas 5 vehicles are capable of flying with as many as five boosters, an option that was employed to generate as much power as possible to launch NASA's New Horizons space probe bound for Pluto.

Tomorrow's flight heads to geosynchronous orbit around Earth to dispatch a new communications satellite for U.S. military forces.

The Russian RD-180 first stage main engine will ignite at T-minus 2.7 seconds, shooting a giant cloud of steam from the pad's main exhaust duct while undergoing a check to ensure its vital signs are healthy. The three strap-on solid rocket boosters are lit at T+plus 0.8 seconds, leading to liftoff at T+plus 1.1 seconds.

The combined power will send the 19-story Atlas vehicle thundering into the morning sky in a hurry. Its fast speed off the launch pad will be remarkably different than other Atlas 5 missions without solid boosters that appear majestically slow.

"Instead of the slow liftoff most people are used to when they see our Atlas 5-401 vehicle launch, this rocket will lift off fairly quickly from the pad in comparison," said Bob Winn, the ULA mission manager.

The Aerojet-made solid boosters will burn for about 90 seconds to assist the RD-180 in propelling the rocket. The SRB casings remain attached to the first stage for another 23 seconds until the rocket reaches a suitable region of flight for jettison.

Once out of the discernible atmosphere, the bulbous nose cone encapsulating the AEHF payload can be shed at T+plus 3 minutes, 27 seconds. The fairing was made by Ruag Space of Switzerland.

The kerosene-fueled first stage will continue to fire until T+plus 4 minutes, 17 seconds. The bronze stage separates about six seconds later, leaving the hydrogen-fueled Centaur upper stage to ignite for a burn lasting nearly 10 minutes that will inject itself into a preliminary orbit.

Centaur completes its first burn over the central Atlantic Ocean and enters an 8-minute coast to the equator. The Pratt & Whitney Rocketdyne RL10 cryogenic engine then restarts for a five-and-a-half-minute firing to propel the spacecraft into the targeted geosynchronous transfer orbit stretching from 119 statute miles at its lowest point to 22,236 statute miles at its highest and inclined 27 degrees to the equator.

Although the Centaur finishes firing by T+plus 27 minutes, 37 seconds, the rocket won't immediately deploy the payload. That milestone moment will wait about 23 minutes as the rocket crosses Africa and Madagascar, eventually flying within communications range of the Diego Garcia tracking station on an island in the Indian Ocean.

"As part of the mission success process that Lockheed Martin and the MILSATCOM folks are working to, they need to have assured telemetry coverage of that critical separation event. That will also enable us to get links for video, to have a forward-facing video view of the spacecraft separation," Winn explained.

Release of the payload from the rocket to complete the launch is expected at T+plus 51 minutes.

Built by Lockheed Martin with help from Northrop Grumman, the AEHF 1 satellite begins the next generation of geosynchronous spacecraft that relay secure communications amongst the national leadership and battlefield commanders.

"AEHF represents a new era of global protected communications that will provide significantly improved, assured connectivity to a greater number of warfighters," said Mike Davis, Lockheed Martin's AEHF vice president.

Designers say one AEHF spacecraft has more capacity than the earlier five-satellite Milstar constellation combined and its faster data rates will benefit tactical military communications, enabling higher quality maps, targeting data and live video to be transmitted without being detected by the enemy.

On the pad! Just 24 hours away from launching a new era in satellite technology for secure and dependable war-time communications to the U.S. military, the Atlas 5 rocket has arrived at the Complex 41 pad for tomorrow's ascent with the AEHF 1 spacecraft.

The two mobile trailers connected to the launching platform, which were part of the convoy during this morning's rollout, soon will be hooked up to power and communications systems at the pad. These trailers provide conditioned air to the payload and communications with the rocket during the rollout and the countdown. They are protected from the blast of launch by a concrete structure on the north-side of the platform.

Within the next hour, the auto couplers between the pad and platform will be engaged to route umbilical connections from the ground to the rocket for tomorrow's fueling of the booster with cryogenic propellants.

Later this morning, the undercarriages used to move the mobile platform will be disconnected and the "trackmobiles" pulled free.

Ground crews will secure the rocket for a quiet afternoon and evening leading into Saturday's launch opportunity.

Countdown clocks will start ticking at 12:07 a.m. EDT as the launch team begins 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 C-band system used to track the rocket as it flies downrange, plus a test of the S-band telemetry relay system. The Complex 41 site will be cleared of all personnel at 4:12 a.m.

A planned half-hour hold begins at 4:27 a.m. when the count reaches T-minus 120 minutes. Near the end of the hold, the team will be polled at 4:54 a.m. to verify all is in readiness to start fueling the rocket for launch.

Supercold liquid oxygen begins flowing into the Centaur upper stage around 5:14 a.m., followed by the first stage filling around 5:27 a.m. 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 starting at 6:53 a.m. That 10-minute 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 morning's 119-minute launch window opens at 7:07 a.m. and closes at 9:06 a.m. EDT.

If the flight is scrubbed for some reason, officials plan to skip over Sunday. The next launch attempt would come Monday between 6:59 and 8:58 a.m. EDT.

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The rocket is passing through the pad entrance gate.

With daybreak lighting the way, the Atlas 5 rocket is emerging from its vehicle assembly building for the journey to the launch pad.

Riding atop a mobile launching platform, the 197-foot-tall space booster is moving to Cape Canaveral's Complex 41 for this critical flight to deploy the first Advanced Extremely High Frequency (AEHF) spacecraft.

The rocket's rollout to the pad has begun.

An Atlas 5 rocket launching the inaugural craft in the U.S. military's new series of secure communications satellites will be rolled the pad in the morning for Saturday's planned liftoff.

The slow half-hour drive from the 30-story Vertical Integration Facility to Cape Canaveral's Complex 41 pad uses 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 two-stage rocket sporting three strap-on solid boosters was put together inside the assembly building this summer. The Advanced Extremely High Frequency (AEHF) spacecraft payload was mounted atop the vehicle last week.

The Atlas 5 is designed to spend minimal time at the launch pad, which does not include a service gantry like other rockets.

Saturday's launch window extends from 7:07 to 9:06 a.m. EDT (1107-1306 GMT).

Weather forecasters are predicting an 80 percent chance of favorable conditions for the space shot.

The outlook includes scattered clouds, a small threat of an isolated shower or thunderstorm, good visibility, westerly winds of 10-14 knots and a temperature around 81 degrees F.

Meteorologists say the only worry will be cumulus clouds associated with a stray rain shower.

Watch this page for complete live countdown and launch coverage!

As expected, this week's Atlas 5 rocket launch has shifted a couple days. Liftoff is rescheduled for Saturday, August 14 during a morning window of 7:07 to 9:06 a.m. EDT.

The rocket will be rolled from its assembly building to the Complex 41 pad on Friday to begin the countdown to launch.

An advanced satellite for relaying secure U.S. military communications and the Atlas 5 rocket that will launch the craft into space next week are being brought together inside a Cape Canaveral assembly building today.

Already packed within the Swiss-made nose cone, the Air Force's first Advanced Extremely High Frequency satellite made a middle-of-the-night departure from its processing hangar in Titusville for a trailer-ride to the rocket's Vertical Integration Facility at Complex 41.

Cranes will hoist the AEHF 1 spacecraft into position atop the rocket for attachment to the Centaur upper stage later in the day.

Read our full story.

A new launch date has been approved for the Atlas 5 rocket. Liftoff is rescheduled for August 12 during a morning window of 7:13 to 9:13 a.m. EDT.

Extra time needed to complete launch preparations will delay the AEHF 1 satellite mission a few days, the Air Force announced today. Liftoff has been retargeted to August 10 during a window of 7:21 to 9:22 a.m. EDT.

Here's the official statement on the postponement:

"This delay was necessary to provide engineers more time to perform confidence testing on a launch vehicle component associated with releasing the fairing support structure. Processing on both the launch vehicle and satellite continues nominally to a new launch date of 10 August. This slip in the AEHF 1 launch is not expected to impact other launches in the manifest."

Now that last week's Falcon-mania has subsided at Cape Canaveral, attention turns to preparations for the Florida spaceport's next launch of the Atlas 5 rocket to place a crucial national security communications satellite into space.

United Launch Alliance technicians have erected the rocket's bronze first stage and the Centaur upper stage aboard the mobile launching platform that's parked inside the Complex 41 assembly building.

Sporting a large nose cone and three strap-on solid-fueled boosters, the vehicle will form one of the most powerful lifters in the U.S. inventory. It's known as the 531 configuration in the Atlas' modular family.

All that thrust will propel the Air Force's first Advanced Extremely High Frequency spacecraft into orbit on July 30 from the Complex 41 launch pad. The morning's window extends from 8:05 to 10:05 a.m. EDT (1205-1405 GMT).

Read our full story.