PHOTOS: Cameras around the pad capture Delta 4-Heavy rocket blasting off today. See the gallery.

PHOTOS: Amazing shots of the Delta 4-Heavy rocket flying away from Vandenberg Air Force Base today. See the gallery.

"The teamwork between the 30th Space Wing, the 4th Space Launch Squadron, the National Reconnaissance Office, United Launch Alliance, and numerous other agencies was outstanding," said Col. Keith Balts, 30th Space Wing commander and the launch decision authority.

"This is Vandenberg's equivalent of an air show or open house and our opportunity to share with the public. We are lucky enough to do this 10-11 times a year."

MISSION SUCCESS! The United Launch Alliance Delta 4-Heavy rocket has successfully launched its classified payload for the U.S. National Reconnaissance Office following liftoff at 11:03 a.m. local time today from Space Launch Complex 6 at Vandenberg Air Force Base, Calif.

"We are truly honored to deliver this critical asset to orbit," said Jim Sponnick, ULA vice president, Atlas and Delta Programs. "The ULA Delta 4-Heavy is currently the world’s largest rocket, providing the nation with reliable, proven, heavy lift capability for our country's national security payloads from both the east and west coasts. I congratulate the combined NRO, Air Force, ULA, and supplier team on today's successful launch of the NROL-65 mission."

The official liftoff time was 11:03:00.224 a.m. local time.

The Delta 4-Heavy rocket has flown into a news blackout. The veil of secrecy surrounding the launch of this clandestine satellite means no further information about the progress of the upper stage engine firings and release of the payload will be announced in real-time.

T+plus 6 minutes, 20 seconds. The nose cone that enclosed the classified National Reconnaissance Office satellite during ascent through the atmosphere has jettisoned.

T+plus 5 minutes, 58 seconds. Engine start! The Aerojet Rocketdyne RL10B-2 cryogenic rocket engine is up and burning for its firing during today's launch of the Delta 4-Heavy.

T+plus 5 minutes, 45 seconds. Pyrotechnics have detonated to jettison the spent center Common Booster Core. The rocket's upper stage and attached payload are now flying free.

T+plus 5 minutes, 32 seconds. Main engine cutoff! The center booster's RS-68 engine has finished firing and shut down.

T+plus 4 minutes, 45 seconds. The center Common Booster Core's RS-68 engine has revved up to full throttle for the Delta 4-Heavy rocket's on-going journey to space. The booster is identical to the outer strap-on stages, carrying the same propellant supply and engine package, but it employed a more conservative fuel consumption strategy over the past three minutes. That has left enough cryogenic fuel to fire nearly 90 seconds longer.

T+plus 4 minutes, 15 seconds. The 15-story tall starboard and port Common Booster Cores that provided the vast majority of thrust during the first four minutes of flight have expended their fuel and peeled away from the center stage. Tiny solid-fueled motors on the discarded boosters gave helpful nudges to ensure a clean separation. The boosters will tumble into the Pacific Ocean below.

T+plus 4 minutes, 10 seconds. Engine cutoff! Standing by for booster separation.

T+plus 3 minutes, 35 seconds. Coming up in about 20 seconds, the outer Common Booster Cores will throttle down as a precursor to engine shutdown and jettison of the stages.

T+plus 3 minutes. The Delta 4-Heavy now weighs half of what it did at liftoff. The rocket is burning vast amounts of cryogenic propellant to accelerate away from the planet.

The center engine remains at partial thrust while the starboard Common Booster Core's engines are firing at full power. The outer boosters have just over one minute remaining in powered flight.

T+plus 2 minutes. The 8-foot diameter bell-shaped nozzles on the three main engines gimbal during flight, allowing the rocket to steer itself on the intended trajectory southward over the Pacific Ocean and toward space.

T+plus 1 minute, 45 seconds. The outer Common Booster Cores and their RS-68 main engines continue to consume the supply of super-cold liquid hydrogen and liquid oxygen rocket fuel while firing at full throttle. The RS-68 is considered the world's largest hydrogen-fueled rocket engine. Each powerplant is capable of generating 17 million horsepower.

T+plus 1 minute, 30 seconds. The vehicle is ascending through the flight regime that provides the maximum aerodynamic pressures on the rocket. This period is called Max-Q. And the Delta 4-Heavy is breaking the sound barrier as its speed reaches Mach 1.

T+plus 55 seconds. The center Common Booster Core's main engine is throttling back to about half-thrust as a fuel conservation effort. The starboard and port boosters continue to operate at their maximum power setting.

T+plus 30 seconds. All three Aerojet Rocketdyne RS-68 main engines are firing at full throttle, gulping three tons of propellant per second to produce 1.9 million pounds of thrust.

T+plus 15 seconds. The vehicle has cleared the towers of the launch pad, majestically firing into the sky with three distinct red-hot main engine plumes trailing 20 stories long for the flight trajectory southward.

LIFTOFF! Liftoff of the United Launch Alliance Delta 4 rocket, providing heavy-lift for the U.S. National Reconnaissance Office!

T-minus 25 seconds. Green board. All systems remain "go" for launch.

T-minus 30 seconds. The terminal countdown sequencer will take control at T-minus 10 seconds. Ignition of the RS-68 powerplants will follow beginning with the starboard engine at T-minus 7 seconds and the center and port engines at T-minus 5 seonds. The engines power up to full thrust for a computer-controlled checkout before liftoff.

T-minus 40 seconds. Upper stage liquid hydrogen tank is confirmed at flight level.

T-minus 55 seconds. The Air Force-controlled Western Range has given its "go" for launch.

T-minus 1 minute and counting. The ignition conditions for three RS-68 main engines are "go."

T-minus 75 seconds. The liquid hydrogen fuel tank on the upper stage is being secured for launch.

T-minus 1 minute, 40 seconds. The CBC liquid hydrogen tanks have reached flight level and pressure.

T-minus 2 minutes. The rocket's upper stage liquid oxygen tank is being secured.

T-minus 2 minutes, 5 seconds. The liquid oxygen tanks in three Common Booster Cores are confirmed at the proper level and pressure for flight.

T-minus 3 minutes and counting. Ordnance devices aboard the vehicle are being armed.

T-minus 3 minutes, 15 seconds. The systems of the Delta 4 rocket have switched from ground-fed power to internal batteries for launch.

T-minus 3 minutes, 25 seconds. Replenishment of liquid hydrogen and liquid oxygen to the Common Booster Cores is being secured in preparation to pressurize the tanks for launch.

T-minus 4 minutes and counting! Clocks are running again for launch of the Delta 4-Heavy rocket on the NROL-65 classified satellite-deployment mission for the National Reconnaissance Office. Liftoff is set to occur at 11:03 a.m. local (2:03 p.m. EDT; 1803 GMT) from Space Launch Complex 6 at Vandenberg Air Force Base, California.

Now six minutes from launch! The ULA launch director has given final approval to resume the countdown as planned.

The government mission director has granted permission to launch.

The final pre-flight poll of the launch team confirms all systems are "ready" for liftoff of the Delta 4-Heavy rocket and its reconnaissance spacecraft payload today. The targeted launch time is 11:03 a.m. local (2:03 p.m. EDT; 1803 GMT).

Now 10 minutes away from the NROL-65 launch for the National Reconnaissance Office.

NEW LAUNCH TIME! The target launch time is being moved to 11:03 a.m. Pacific (2:03 p.m. EDT; 1803 GMT). The team is resolving a couple of minor issues.

Assuming all systems remain go, clocks will resume ticking at 10:49 a.m. Pacific Time. During those final four minutes, the rocket will switch to internal power, ordnance will be armed, all eight propellant tanks will be secured and the Range will announce a clear-to-launch.

In the final moments, the sparkler-like radial outward firing ignitors -- or ROFIs -- are started beneath the main engine nozzles. The Terminal Countdown Sequencer will grab control at T-minus 10 seconds to manage events in the crucial last seconds and oversee the rocket's status. The ignition sequence for the three RS-68 powerplants follows at T-minus 7 seconds for the starboard booster and T-minus 5 seconds for the center and port as the main hydrogen fuel valve in each engine is opened. As fuel floods through the engines, flame erupts at the base of the rocket as free hydrogen reaches the ROFIs.

The oxygen valves in the engines are opened a couple of seconds later as the RS-68s begin roaring to life. The engines must rev up to full throttle -- 102 percent thrust level -- and undergo a rapid computer-controlled health check to ensure all parameters are met.

If any problem is detected before T-minus 40 milliseconds, the engines will shut down and the rocket prevented from lifting off.

A successful engine startup leads to T-0 as the 12 hold-down bolts that have been restraining the rocket to Earth finally detonate. The 23-story, 1.6-million pound vehicle blasts off at 10:53 a.m. PDT (1:53 p.m. EDT) on the NROL-65 spy satellite deployment mission.

A load relief file based on the upper level winds is being transmitted to the Delta 4 rocket's flight computer. This program informs the rocket on the wind conditions it can expect to see during ascent.

The countdown is entering the final 30 minutes until the Delta 4-Heavy rocket launch from Vandenberg Air Force Base at 10:53 a.m. local time. Here's a look at some stats about today's mission. This will be:

• The 364th Delta rocket launch since 1960
• The 24th Delta 4 rocket mission since 2002
• The 7th Heavy configuration to fly
• The 36th-37th-38th main engines from RS-68 family used
• The 439th production RL10 engine to be launched
• The 27th RL10B-2 engine launched
• The 5th Delta 4 rocket launch from Vandenberg
• The 2nd Heavy launch from Vandenberg
• The 63rd Evolved Expendable Launch Vehicle flight
• The 74th United Launch Alliance mission since 2006
• The 17th Delta 4 under the ULA banner
• The 8th ULA launch this year
• The 3rd launch of the Delta family in 2013
• The 20th use of Delta 4 by the Air Force
• The 8th classified Delta 4 for the NRO

Steering checks of the Delta 4 rocket's engines are complete and satisfactory. The upper stage RL10 engine and the three Common Booster Core main engines were put through slew tests to confirm the rocket will be able to steer itself properly during ascent.

The thermal insulation inspections have been completed following fueling and there were no problems reported today.

T-minus 4 minutes and holding. The countdown has just entered a planned hold point. Clocks will remain here for 45 minutes and 30 seconds, synching up with the new launch time. This pre-scheduled hold is designed to give the launch team members a chance to finish any work running behind schedule and for mission officials to conduct final readiness polls.

T-minus 10 minutes. The countdown clocks will be going into a planned hold at the T-minus 4 minute mark. Liftoff remains targeted for 10:53 a.m. local time, a slight change from earlier.

The team is preparing to conduct steering checks of the Delta 4 rocket's engines.

One hour to go!

Propellant conditioning is being achieved on the various vehicle tanks.

NEW LAUNCH TIME! The target launch time is being adjusted slightly to 10:53 a.m. Pacific (1:53 p.m. EDT; 1753 GMT).

Radio frequency link checks are being performed to verify good telemetry streams between the rocket and the receiving stations.

Now 90 minutes left to go. As the countdown proceeds toward launch this morning, you can follow along right here on this page.

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All eight propellant tanks are loaded, meaning the Delta 4-Heavy rocket now stands fully fueled for launch.

Checks of the safety system between the vehicle and Range have been completed satisfactorily.

Loading of the upper stage liquid hydrogen tank just wrapped up.

Two hours and counting as the United Launch Alliance team works to get the Delta 4-Heavy rocket fully fueled with cryogenic propellants for today's launch. Liftoff remains scheduled for 10:52 a.m. Pacific Time.

Post-loading checks of the Common Booster Core liquid oxygen systems have been accomplished. The team is going right into upper stage LOX checks after loading that tank with 4,500 gallons.

There are no issues being reported at this point in the countdown, fueling activities are in the home stretch and clocks are ticking on schedule to the 10:52 a.m. local launch time at Vandenberg Air Force Base.

Loading of the liquid hydrogen tanks on the three Common Booster Cores in fast-fill mode has been completed. Some 110,000 gallons of LH2 are put into the rocket's tanks for flight. Vent and relief checks will be performed shortly.

Three hours and counting!

The launch team has completed chilldown and started the upper stage liquid oxygen loading. This is the last tank left to fill today.

The loading of liquid oxygen into the Common Booster Cores just finished. The launch team will be performing vent and relief checks following tanking and begin procedures for the upper stage liquid oxygen system.

Loading of the upper stage liquid hydrogen supply is underway. The tank will be filled with 10,000 gallons of propellant for the RL10 engine.

With the CBC liquid hydrogen tanking continuing, the launch team has been given approval to begin chilldown conditioning of the upper stage liquid hydrogen system. This is a precursor to fueling the upper stage.

At this point in the countdown, technicians are conducting testing of the C-band tracking beacon and GPS antenna checks for flight.

The liquid oxygen loading is progressing for the three Common Booster Cores as the fast-fill is starting. Each tank will be loaded with about 40,000 gallons of supercold LOX.

Now four hours till launch. The Delta 4 rocket's three Common Booster Cores currently are being loaded with super-cold liquid oxygen and liquid hydrogen propellants.

Space Launch Complex 6 has two giant sphere-shaped fuel tanks to store the cryogenic liquid oxygen and liquid hydrogen. The LOX tank holds 250,000 gallons and LH2 sphere about 850,000 gallons.

The cryogenics are fed from the storage tanks through pipelines to the pad. For the three Common Booster Cores, the propellants are routed up to the launch table upon which the rocket sits. Tail service masts, the large box-like structures at the base of the vehicle, feed the oxygen and hydrogen to the boosters via separate umbilicals. The upper stage receives its cryos from the top swing arm that extends from the Fixed Umbilical Tower to the front-side of the rocket.

With the Common Booster Cores' liquid oxygen systems properly conditioned for cryogenic temperatures, the loading of Minus-298 degree LOX into the Delta 4-Heavy rocket is beginning. The liquid oxygen tanks in all three Common Booster Cores will be filled over the next hour or so. The oxidizer will be consumed by the main engines during launch.

The liquid hydrogen loading is switching to the "fast-fill" mode as planned.

And now the liquid oxygen chilldown is starting in advance of feeding the cryogenic oxidizer into the Delta 4-Heavy rocket.

The cold gas chilldown for the hydrogen side has been completed and the launch team is beginning the initial loading of liquid hydrogen propellant into the three Common Booster Core stages. This "slow-fill" will be sped up to "fast-fill" after a small portion of each tank is loaded.

Chilled to Minus-423 degrees Fahrenheit, the liquid hydrogen will be consumed by the main engines, along with liquid oxygen during the early minutes of launch.

The fueling operations are getting underway. The cold gas chilldown conditioning of the Common Booster Cores for liquid hydrogen loading has begun.

The pad team has successfully resolved the hydraulic cooling valve issue and departed the pad. With that, approval has been given to resume operations this morning for fueling.

The launch team will start the thermal conditioning steps to ready equipment for pumping the super-cold liquid oxygen and liquid hydrogen propellants into the Delta 4-Heavy rocket today.

Here's some pictures taken at Space Launch Complex 6 earlier this morning after rollback of the mobile service gantry. The images can be seen here.

Fueling will be placed on hold for a little while as a special team is dispatched to the pad. Workers need to adjust the system that is keeping a cooling valve in the vehicle hydraulics from opening fully.

T-minus 5 hours, 15 minutes and counting! The countdown has commenced for the Delta 4-Heavy rocket on the NROL-65 mission to serve the U.S. National Reconnaissance Office. With one final hold planned at T-minus 4 minutes, lasting 45 minutes, liftoff is targeted to occur at 10:52 a.m. Pacific Time.

The multi-step process of loading all eight cryogenic propellant tanks in the rocket is scheduled to begin shortly.

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The launch team has been polled to ensure all stations are manned and systems are ready to proceed into the countdown. No issues are being reported and activities are tracking right on the planned timeline this morning.

T-minus 5 hours, 15 minutes and holding. A pre-planned 15-minute hold has started ahead of the Terminal Countdown sequence. During this time the full launch team will be seated at the consoles, the pad is scheduled to be cleared of all workers and readiness polls will be conducted by mission management to ensure everyone is ready to proceed.

The count begins when the clocks resume ticking at 4:52 a.m. local (7:52 a.m. EDT), leading toward a liftoff of the Delta 4-Heavy rocket at 10:52 a.m. (1:52 p.m. EDT) from Vandenberg Air Force Base, California.

The weather forecast has worsened to 60 percent favorable due to cumulus clouds and the addition of the liftoff winds as a possible constraint.

The outlook calls for tropical storm moisture moving out of the area in the morning, the marine layer held in place by an on-shore flow, winds more northerly than originally forecast at 12 to 18 knots and a temperature in the mid 60s.

All systems remain "go" for Wednesday's launch of the Delta 4-Heavy rocket, America's largest unmanned space booster, carrying a reconnaissance satellite for U.S. national security.

The weather outlook now predicts an 80 percent chance of acceptable conditions for the 10:52 a.m. local (1:52 p.m. EDT; 1752 GMT) launch time. Cumulus clouds pose only a slight concern for violating launch rules.

The 23-story vehicle roar will into the sky on nearly two million pounds of ground-shaking thrust, departing Space Launch Complex 6 on the southern end of Vandenberg Air Force Base.

"This will be the second Delta 4-Heavy launched from Vandenberg," said Col. Keith Balts, 30th Space Wing commander and the launch decision authority.

"We are excited to showcase this national capability for heavy lift on the Western Range in support of the NRO. This is what makes Vandenberg unique because we provide the full spectrum of space lift capabilities from smaller launch vehicles up to and including the Delta 4-Heavy."

The triple-wide rocket will trail fiery plumes from the three main engines as it majestically climbs into the late-morning sky and heads downrange on a southward trajectory over the Pacific.

The forecast marine layer could hamper the view for spectators near the base, however.

Crews at Space Launch Complex 6 have retracted the 27-story mobile assembly shelter away from the rocket. This 9-million-pound structure, which moves along rails, was built in the 1980s when the pad was being prepared for space shuttle launches. It was designed to shield the shuttle from the weather during on-pad assembly of the vehicle's solid rocket boosters, external tank and mating of the orbiter.

Late tonight, the 32-story, 13-million-pound mobile service tower that actually wraps around the Delta 4-Heavy to provide workers access to the rocket will be rolled back to fully unveil the space launcher.

The countdown starts at 4:52 a.m. local and fueling operations begin just after 5 a.m.

Weather forecasters expect the marine layer to be draped over Vandenberg Air Force Base on Wednesday morning for the launch of the Delta 4-Heavy rocket.

Tropical storm remnants moving into the region are predicted to bring increased cloud cover for the Central Coast and thunderstorms over the mountains to the southeast.

There is a 70 percent chance of acceptable conditions for launch. Cumulus clouds are the main concern.

Winds at the launch pad will be north to northwesterly from 12 to 18 knots and see a temperature in the mid 60s.

Igniting its three main engines in a staggered sequence for the first time, a United Launch Alliance Delta 4-Heavy rocket for U.S. national security is scheduled for liftoff from California on Wednesday morning.

A new strategy, being employed to reduce the hydrogen flames generated during startup of the three Aerojet Rocketdyne RS-68 main engines, will see the triple-body rocket light one engine two seconds before the other two.

Read our full story.

LAUNCH TIME. The target launch time for next Wednesday's Delta 4-Heavy rocket from California has been announced to the public. Liftoff from Vandenberg Air Force Base is scheduled for 10:52 a.m. local (1:52 p.m. EDT; 1752 GMT).

The exact duration of the daily launch window hasn't been disclosed. However, officials previously said liftoff would happen some time between 10 a.m. and 12 noon local time.

The payloads are attached and final preparations are underway for two national security satellites heading for different orbits aboard United Launch Alliance Delta 4 rockets in August, one from Cape Canaveral, the other at Vandenberg Air Force Base in California.

Read our full story.

United Launch Alliance and the Air Force are readying the next Delta 4-Heavy rocket, the largest booster in the U.S. arsenal that is responsible for launching the nation's elite surveillance satellites.

The massive rocket was placed atop its West Coast pad this week, rolling out of the hangar at Vandenberg Air Force Base in California on Monday and going vertical Tuesday for a high-profile mission to deliver a National Reconnaissance Office spacecraft into polar orbit.

Liftoff is targeted for Aug. 28.

Read our full story.