The Ariane 5 rocket has achieved its 51st consecutive successful launch since 2003 and the vehicle's 61st overall success in 65 flights since 1996.

Plus+30 minutes, 41 seconds. SPACECRAFT SEPARATION! The GSAT 10 communications satellite has been released from the Ariane 5 rocket's upper stage, completing today's launch.

Designed and built by the Indian Space Research Organization, the spacecraft will join the Indian National Satellite system from geostationary orbit at 83 degrees East.

It is headed for geostationary orbit a slot of 83 degrees East longitude for its 15-year mission using 18 C-band and 12 Ku-band transponders for television and telecommunications services across the Indian subcontinent. The craft, weighing 7,497 pounds at launch, also carries a GPS-aided navigation payload for aircraft use throughout Indian airspace.

Plus+29 minutes, 45 seconds. Ariane is 1,402 km in altitude.

Plus+29 minutes. The barrel-like "Sylda" payload adapter between ASTRA 2F and the GSAT 10 satellites has been jettisoned. This has exposed GSAT for its upcoming release from the rocket.

Plus+28 minutes. Ariane is 1,077 km in altitude.

Plus+27 minutes, 20 seconds. SPACECRAFT SEPARATION! The ASTRA 2F spacecraft has been released from the Ariane 5 rocket's upper stage, beginning a planned 15-year life span.

Built by Astrium using the Eurostar E3000 satellite design, the craft is equipped with Ku-band and Ka-band transponders to provide direct-to-home television broadcasting to Europe, the Middle East and Africa. The 13,157-pound satellite will be maneuvered into geostationary orbit for use by the SES Group of Luxembourg. The ASTRA constellation serving more than 135 million households via satellite and cable TV networks.

It will replace the aging ASTRA 2B, which was launched by Ariane 5 in September 2000 at the orbital position of 28.2 degrees East longitude.

Plus+26 minutes, 15 seconds. Altitude is 792 km, velocity is 9.2 km/sec.

Plus+25 minutes, 25 seconds. The cryogenic upper stage for Ariane 5 has just shut down to complete its burn for today's launch. The stage will prepare for deployment of the two satellite payloads a few minutes from now.

Plus+24 minutes, 30 seconds. Ariane is 562 km in altitude and traveling at 9.27 km/sec.

Plus+23 minutes, 45 seconds. Ariane is 492 km in altitude and traveling at 9.1 km/sec.

Plus+23 minutes, 15 seconds. Two minutes of propulsion remains in the upper stage.

Plus+22 minutes, 55 seconds. Ariane is 406 km in altitude and traveling at 9.0 km/sec.

Plus+21 minutes, 50 seconds. Ariane is 325 km in altitude and traveling at 8.8 km/sec.

Plus+20 minutes, 30 seconds. Ariane is 252 km in altitude and traveling at 8.6 km/sec.

Plus+20 minutes. Just over five minutes remain in this firing of the upper stage.

Plus+19 minutes. Ariane is 197 km in altitude and traveling at 8.4 km/sec.

Plus+17 minutes. Ariane is 160 km in altitude and traveling at 8.1 km/sec.

Plus+16 minutes. The vehicle is on the upward climb again. Ariane is 152.6 km in altitude and traveling at 7.9 km/sec.

Plus+15 minutes. Altitude is 149 km, velocity is 7.8 km/sec.

Plus+14 minutes. Ariane is 150 km in altitude and traveling at 7.6 km/sec.

Plus+12 minutes, 55 seconds. Ariane is 153 km in altitude and traveling at 7.46 km/sec.

Plus+11 minutes, 50 seconds. Ariane is 157 km in altitude and traveling at 7.3 km/sec.

Plus+11 minutes, 30 seconds. The cryogenic upper stage motor continues to fire as the rocket starts the next portion of the trajectory where it gives up a little bit of altitude to obtain even quicker speeds.

Plus+10 minutes, 55 seconds. Ariane is 161 km in altitude and traveling at 7.1 km/sec.

Plus+9 minutes, 50 seconds. Ariane is 164 km in altitude and traveling at 7.0 km/sec.

Plus+9 minutes, 18 seconds. The upper stage of the Ariane 5 ECA rocket is up and burning to accelerate the payload into geosynchronous transfer orbit.

Plus+9 minutes, 8 seconds. The main cryogenic stage's Vulcain engine has cut off and the spent stage has separated. It will fall back into the atmosphere.

Plus+8 minutes. Coming up on main stage shutdown in about one minute. Velocity is 5.6 km/sec.

Plus+7 minutes, 45 seconds. Ariane is 168.4 km in altitude and traveling at 5.27 km/sec.

Plus+7 minutes, 15 seconds. The rocket's climb has leveled out as designed. This temporary trajectory is needed in order to gain speed.

Plus+7 minutes. Ariane is 170 km in altitude and traveling at 4.5 km/sec.

Plus+6 minutes. The main stage's Vulcain 2 engine continues to fire as it burns a mixture of liquid hydrogen and liquid oxygen rocket fuel.

Plus+5 minutes. Ariane is 156 km in altitude and traveling at 3.0 km/sec.

Plus+4 minutes. Ariane remains right on course. The rocket is 135 km in altitude and traveling at 2.5 km/sec.

Plus+3 minutes, 30 seconds. Separation of the rocket's nose cone has been confirmed, uncovering the ASTRA 2F satellite in its upper position in the dual payload stack.

Plus+3 minutes. The vehicle is 98 km in altitude, traveling at 2.1 km/sec.

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+2 minutes. A beautiful early evening ascent by Ariane 5!

Plus+1 minute, 30 seconds. Less than a minute left in the burn by the solid rocket boosters. The boosters are providing 90 percent of the liftoff thrust.

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

Plus+35 seconds. Pitch and roll maneuvers has been performed by the Ariane 5 vehicle to position itself on the correct eastward trajectory bound for its highly elliptical orbit to drop off two telecommunications satellites.

LIFTOFF! Liftoff of ASTRA 2F and GSAT 10, a dual-satellite payload for Europe and India, as the 65th Ariane 5 rocket clears the tower!

Minus-50 seconds. The vehicle is running on internal power.

Minus-1 minute. Final 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 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 2 main engine supply valves are being opened. And the ground valves for engine chilldown are being closed.

Minus-3 minutes. The upper stage cryogenic tanks are charging to flight pressures. And the scheduled launch time has been loaded into the rocket's main computer system.

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

Minus-5 minutes. Still heading for an on-time launch.

Minus-6 minutes and counting. Liquid hydrogen and liquid oxygen supplies of the main and upper cryogenic stages are being topped off at flight levels. Also, the pyrotechnic line safety barriers are being armed.

Minus-7 minutes and counting. The Synchronized Sequence is starting. Computers are now in control of this final segment of the launch countdown to prepare the rocket and ground systems for liftoff. There are two computers running the countdown -- one aboard the Ariane 5 and a redundant one at the ELA-3 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-12 minutes and counting. No launch constraints are being reported with the Ariane rocket, its double satellite payload, ground systems or the weather. The Synchronized Sequence will assume control of the clock at 2118 GMT to govern the final seven minutes to launch.

Minus-15 minutes and counting. ASTRA 2F is the 28th Eurostar E3000 satellite built by Astrium to be launched. And ISRO's GSAT 10 will join eight other spacecraft in the Indian National Satellite system that was established in 1983.

Minus-20 minutes and counting. Today's mission represents the 65th launch for the Ariane 5 rocket dating back to 1996 and the fifth this year. It is the 209th flight overall for the Ariane family of launchers since 1979.

What's more, it is the 36th SES spacecraft entrusted to Arianespace over the past quarter-century and the 15th satellite from the Indian Space Research Organization to fly on the European launcher since 1981.

Welcome to our live launch coverage of Ariane 5 with the ASTRA 2F and GSAT 10 payloads. Liftoff remains scheduled for 2118 GMT from the Guiana Space Center in Kourou, French Guiana on the northeastern coast of South America.

The Ariane 5 rocket is fully fueled, weather is GO and no technical problems are being reported in the countdown.

A European television satellite and an Indian-made telecommunications spacecraft will share a ride into orbit today atop the commercial Ariane 5 rocket on a heavy-duty mission carrying over 20,000 pounds of payload.

Traveling the 1.7-mile trek on rails, the 16-story-tall Ariane 5 was rolled out Thursday from its final assembly building where the two payloads had been mounted atop the vehicle.

Today's liftoff, unleashing 2.6 million pounds of thrust from its hydrogen-fueled main stage and twin solid rocket boosters, is scheduled for 5:18 p.m. EDT (2118 GMT). The day's available launch window extends 47 minutes to 6:05 p.m.

Join is for live updates and streaming video of the launch on this page starting about 20 minutes before liftoff time.

Bound for a typical geosynchronous transfer orbit, the rocket will first deploy the ASTRA 2F craft to provide direct-to-home TV broadcasting capabilities across Europe, the Middle East and Africa, then release the GSAT 10 satellite that will provide a range of communications services and navigation signals across India.

The two satellites, plus the dual-payload adapter equipment amount to 22,440 pounds, including 20,654 pounds just for the two spacecraft. That is near the weight record for Ariane 5 going to geosynchronous transfer orbit, just 10 pounds less than the previous mission.

The countdown clock was started by Arianespace today at 5:48 a.m. EDT and a complete check of electrical systems occurred at 9:48 a.m. EDT.

Fueling of the Ariane 5 with super-cold liquid hydrogen and liquid oxygen propellants begins at 12:28 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 tanks contained within the rocket's main stage.

A similar procedure for the Ariane 5's cryogenic upper stage will commence at 1:28 p.m. EDT.

Chilldown conditioning of the Vulcain 2 first stage engine will occur at 1:58 p.m. EDT, and a communications check between the rocket and ground telemetry, tracking and command systems is scheduled for 4:08 p.m. EDT.

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

The Vulcain 2 main engine ignites as the countdown reaches zero, followed by a health check and lighting 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 pair of solid rocket boosters will jettison at T+plus 2 minutes and 21 seconds some 42 miles in altitude.

Once above the dense atmosphere, the launcher's payload fairing will fall away more than three minutes into flight at an altitude of 68 miles. The Ariane 5's first stage will shut down at T+plus 8 minutes, 59 seconds, followed moments later by stage separation and ignition of the hydrogen-fueled cryogenic HM7B upper stage engine all at altitude of 102 miles.

The rocket's upper stage will fire for nearly 16 minutes, accelerating to a velocity of 20,915 miles per hour to reach an elliptical orbit with an advertised high point of 22,330 miles, a low point of 155 miles and inclination of 6 degrees relative to the equator.

The release of ASTRA 2F is scheduled for T+plus 27 minutes, 44 seconds. The rocket's barrel-like Sylda 5 dual-payload adapter will be jettisoned 29 minutes into the flight to uncover the second passenger.

GSAT 10 will separate from the lower portion of the payload stack at T+plus 30 minutes, 45 seconds, capping the ascent.