The Ariane 5 rocket has achieved its 49th consecutive successful launch since 2003 and the vehicle's 59th overall success in 63 flights since 1996.

Plus+34 minutes, 20 seconds. MSG 3 separation confirmed as launch officials erupt in applause inside the Jupiter control room at the Guiana Space Center.

Plus+31 minutes, 30 seconds. The Sylda 5 payload adapter has been released.

Plus+29 minutes. The barrel-shaped Sylda payload adapter will jettison in about 2 minutes, exposing the MSG 3 satellite, which rode the Ariane 5 launcher in the lower position in its dual-payload configuration.

MSG 3's separation is scheduled for Plus+34 minutes, 11 seconds.

Plus+27 minutes, 50 seconds. Arianespace confirms the EchoStar 17 satellite has separated to begin a mission beaming broadband Internet services to North America for Hughes Network Systems.

Plus+25 minutes. The second stage engine has cut off on schedule.

Deployment of EchoStar 17, the first of the launch's payloads to be released, will come at Plus+27 minutes, 35 seconds.

Plus+21 minutes. The upper stage will shut down at Plus+24 minutes, 58 seconds, after reaching a target orbit with a low point of 155 miles, a high point of 22,334 miles, and an inclination of 6 degrees.

Plus+19 minutes. The rocket is now flying 130 miles high at a velocity of more than 18,800 mph. The vehicle is now in range of communications stations in Africa after flying across the Atlantic Ocean.

Plus+17 minutes. The cryogenic HM7B engine continues to peform well.

Plus+12 minutes. This upper stage engine burn will last nearly 16 minutes.

Plus+9 minutes, 15 seconds. The main cryogenic stage's Vulcain engine has cut off and the spent stage has separated. It will fall back into the atmosphere prior to completing an orbit of Earth.

And the upper stage's HM7B engine is now firing to inject the EchoStar 17 and MSG 3 satellites into orbit.

All systems are reported to be in good shape, and the Ariane 5 is flying right on course.

Plus+3 minutes, 20 seconds. Separation of the rocket's nose cone has been confirmed.

The Ariane 5 core stage will continue burning until about Plus+9 minutes into the mission.

Plus+2 minutes, 22 seconds. The solid rocket boosters have been jettisoned from the Ariane 5 rocket's core stage. The liquid-fueled Vulcain 2 main engine continues to fire to propel the vehicle and its satellite payload to space.

Plus+60 seconds. The vehicle is on the proper heading as it rides the power of the twin solid rocket boosters and main stage liquid-fueled engine.

LIFTOFF of the Ariane 5 rocket from French Guiana with payloads to serve Internet to North America and provide European forecasters with satellite imagery.

Minus-1 minute. A fast-paced series of events leading to launch will begin at Minus-37 seconds when the automated ignition sequence is started. The water suppression system at the launch pad will start at Minus-30 seconds. At Minus-22 seconds, overall control will be given to the onboard computer. The Vulcain main engine will be readied for ignition with hydrogen chilldown starting at Minus-18 seconds.

The residual hydrogen burn flares will fire beneath the Vulcain engine at Minus-6 seconds to burn away any free hydrogen gas. At Minus-3 seconds, onboard systems take over and the two inertial guidance systems go to flight mode. Vulcain main engine ignition occurs at Minus-0 seconds with checkout between Plus+4 and 7 seconds. If there are no problems found, the solid rocket boosters are ignited at Plus+7.0 seconds for liftoff at Plus+7.3 seconds.

Minus-2 minutes. The Vulcain main engine supply valves are being opened. And the ground valves for engine chilldown are being closed.

Minus-3 minutes. The scheduled launch time has been loaded into the rocket's main computer system. The main stage tank pressures should now be at flight level.

Minus-4 minutes. Pressurization is now underway for the main cryogenic stage's liquid oxygen and hydrogen tanks. Also, final pyrotechnic arming is starting.

Minus-5 minutes. All status panel lights remain green, indicating no problems right now that could prevent an on-time blastoff.

Minus-6 minutes. Liquid hydrogen and liquid oxygen supplies of the main cryogenic stage are being verified at flight level. Also, the pyrotechnic line safety barriers are being armed.

Minus-7 minutes and counting. The synchronized sequence has started. Computers are now in control of this automated final phase of the launch countdown to prepare the rocket and ground systems for liftoff. There are three computers running the countdown -- one aboard the Ariane 5 and two redundant computers at the launch complex.

Minus-10 minutes and counting. Still all green across the status board in launch control as the countdown heads for the synchronous sequence.

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Minus-20 minutes. The Synchronized Sequence is being prepped for activation. This computer-run sequence assumes control of the countdown at the Minus-7 minute mark to perform the final tasks to place the rocket and pad systems in launch configuration. At Minus-4 seconds, the rocket's onboard computer will take over control of main engine start, health checks of the powerplant and solid rocket booster ignition commanding for liftoff.

Minus-60 minutes. The live video stream from French Guiana will begin 20 minutes before liftoff, which remains set for 2136 GMT (5:36 p.m. EDT; 6:36 p.m. French Guiana time).

With all systems and weather in good shape for launch, fueling of the Ariane 5 rocket's first and second stages is underway. The rocket's core burns cryogenic propellant, while two solid-fueled strap-on boosters will help power the rocket from the pad.

An Ariane 5 rocket rolled to its launch pad in French Guiana on Wednesday, moving closer to liftoff Thursday with the EchoStar 17 high-throughput broadband communications satellite for North America and Europe's MSG 3 geostationary weather observatory.

After reaching the launch pad, the rocket was connected to ground utilities, including electrical and fueling systems. Workers at the South America launch site filled the Ariane 5's helium pressurant system later Wednesday.

Liftoff from the Guiana Space Center's ELA 3 launch zone is set for 2136 GMT (5:36 p.m. EDT; 6:36 p.m. French Guiana time) Thursday. The launch window extends for 29 minutes.

The EchoStar 17 and MSG 3 payloads are stacked inside the Ariane 5's aerodynamic nose shroud.

EchoStar 17, built by Space Systems/Loral, will expand high-speed broadband Internet capacity over North America for the HughesNet service operated by Hughes Network Systems.

Manufactured by Thales Alenia Space for Eumetsat, Europe's weather satellite agency, the MSG 3 satellite is the third of four current-generation Meteosat observatories planned to launch through 2014.

MSG 3 will collect highly-detailed imagery of Europe, the North Atlantic, and Africa every 15 minutes for use by weather forecasters.

Final Ariane 5 countdown procedures are scheduled to begin began around 1006 GMT (6:06 a.m. EDT). A check of electrical systems occurred around 1406 GMT (10:06 a.m. EDT).

Workers will also put finishing touches on the launch pad, including the closure of doors, removal of safety barriers and configuring fluid lines for fueling.

The launch team will begin the process to fuel the rocket with super-cold liquid hydrogen and liquid oxygen propellants at 1636 GMT (12:36 p.m. EDT). First, ground reservoirs will be pressurized, then the fuel lines will be chilled down to condition the plumbing for the flow of super-cold liquid hydrogen and liquid oxygen, which are stored at minus 423 degrees Fahrenheit and minus 298 degrees Fahrenheit, respectively.

It will take approximately two hours to fill the Ariane 5 core stage tanks.

A similar procedure for the Ariane 5's cryogenic upper stage will commence at 1736 GMT (1:36 p.m. EDT).

Chilldown conditioning of the Vulcain 2 first stage engine will occur at 1836 GMT (2:36 p.m. EDT), and a communications check between the rocket and ground telemetry, tracking and command systems is scheduled for 2026 GMT (4:26 p.m. EDT).

The computer-controlled synchronized countdown sequence will begin seven minutes before launch to pressurize propellant tanks, switch to on-board power and take the rocket's guidance system to flight mode.

The Vulcain 2 engine will ignite as the countdown clock reaches zero, followed by a health check and ignition of the Ariane 5's solid rocket boosters seven seconds later to send the 1.7 million-pound launcher skyward.

Five seconds after blastoff, the rocket will begin pitching east from the ELA-3 launch pad, surpassing the speed of sound less than a minute into the mission. The Ariane 5's twin solid rocket boosters will jettison 2 minutes and 22 seconds after liftoff.

Once above the dense atmosphere, the launcher's payload fairing will fall away at an altitude of about 66 miles. The Ariane 5's first stage will shut down at 8 minutes, 59 seconds, followed moments later by stage separation and ignition of the hydrogen-fueled cryogenic HM7B upper stage engine.

The rocket's upper stage will fire for nearly 16 minutes, accelerating to a velocity of 5.8 miles per second to reach an orbit with a planned high point of 22,344 miles and a targeted low point of 155 miles.

The release of EchoStar 17 is scheduled for 27 minutes, 34 seconds. The rocket's barrel-shaped Sylda 5 dual-payload adapter will be jettisoned a few minutes later.

MSG 3 will separate from the lower portion of the payload stack at 34 minutes, 11 seconds.

Check out these photos of the Ariane 5 rocket poised on the launch pad after rollout yesterday.