The next Ariane 5 launch is targeted for June 19 carrying the EchoStar 17 and MSG 3 spacecraft. EchoStar 17, formerly known as Jupiter 1, will provide high-throughput broadband services across North America for Hughes Network Systems. MSG 3 is a geostationary weather satellite for Eumetsat, the European satellite meteorology agency.

The Ariane 5 rocket has achieved its 48th consecutive successful launch since 2003 and the vehicle's 58th overall success in 62 flights since 1996.

Plus+36 minutes, 8 seconds. SPACECRAFT SEPARATION! The VINASAT 2 communications satellite has been released from the Ariane 5 rocket's upper stage, completing today's launch.

The VINASAT 2 spacecraft will be used by Vietnam Posts and Telecommunications Group to relay TV, phone and radio signals.

It is headed for an orbital slot of 131.8 degrees East longitude for its mission exceeding 15 years to broaden the telecommunications offerings of its operator in Vietnam and neighboring countries. The craft, weighing 6,546 pounds at launch, carries 24 Ku-band transponders.

Vietnam Posts and Telecommunications Group deployed its first satellite, VINASAT 1, in April 2008.

Plus+35 minutes, 8 seconds. The barrel-like "Sylda" payload adapter between JCSAT 13 and the VINASAT 2 satellites has been jettisoned. This has exposed VINASAT 2 for its upcoming release from the rocket.

Plus+34 minutes. Ariane is 2,403 km in altitude.

Plus+33 minutes. Coming up on jettison of the rocket's dual payload adapter about two minutes from now.

Plus+32 minutes. Ariane is 1,947 km in altitude.

Plus+31 minutes. Ariane is 1,731 km in altitude.

Plus+29 minutes, 30 seconds. Ariane is 1,429 km in altitude.

Plus+28 minutes, 30 seconds. Ariane is 1,231 km in altitude.

Plus+27 minutes, 30 seconds. Ariane is 1,052 km in altitude.

Plus+26 minutes, 43 seconds. SPACECRAFT SEPARATION! The JCSAT 13 direct-to-home television broadcasting satellite has been released from the Ariane 5 rocket's upper stage.

JCSAT 13 carries 44 Ku-band transponders to serve Japan's SKY Perfect JSAT Corporation. The 9,983-pound satellite was built by Lockheed Martin using the A2100 design. It has a 15-year life expectancy.

It will replace the aging JCSAT 4A, originally launched aboard an Atlas 2AS rocket from Cape Canaveral in February 1999, in coverage to Japan and Southeast Asia from an orbital position of 124 degrees East longitude.

Plus+25 minutes, 35 seconds. Altitude is 750 km, velocity is 9.27 km/sec.

Plus+25 minutes, 7 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 607 km in altitude and traveling at 9.26 km/sec.

Plus+23 minutes, 45 seconds. Ariane is 525 km in altitude and traveling at 9.15 km/sec.

Plus+23 minutes, 15 seconds. Less than two minutes of propulsion remains in the upper stage.

Plus+22 minutes, 30 seconds. Ariane is 416 km in altitude and traveling at 8.95 km/sec.

Plus+21 minutes, 30 seconds. Ariane is 352 km in altitude and traveling at 8.79 km/sec.

Plus+20 minutes, 45 seconds. Ariane is 314 km in altitude and traveling at 8.66 km/sec.

Plus+20 minutes, 15 seconds. Just under five minutes remain in this firing of the upper stage.

Plus+19 minutes, 15 seconds. Ariane is 261 km in altitude and traveling at 8.42 km/sec.

Plus+18 minutes, 30 seconds. Ariane is 242 km in altitude and traveling at 8.29 km/sec.

Plus+17 minutes, 55 seconds. Ariane is 230 km in altitude and traveling at 8.2 km/sec.

Plus+17 minutes, 15 seconds. Ariane is 220 km in altitude and traveling at 8.0 km/sec.

Plus+16 minutes. Ariane is 206 km in altitude and traveling at 7.89 km/sec.

Plus+15 minutes. The vehicle is on the upward climb again. Altitude is 199.9 km, velocity is 7.73 km/sec.

Plus+14 minutes. Ariane is 196.8 km in altitude and traveling at 7.58 km/sec.

Plus+12 minutes, 55 seconds. Ariane is 196 km in altitude and traveling at 7.41 km/sec.

Plus+12 minutes, 15 seconds. Ariane is 196.5 km in altitude and traveling at 7.3 km/sec.

Plus+11 minutes, 30 seconds. Ariane is 197.6 km in altitude and traveling at 7.2 km/sec.

Plus+11 minutes. 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, 30 seconds. Ariane is 199.4 km in altitude and traveling at 7.05 km/sec.

Plus+9 minutes, 45 seconds. Ariane is 200.6 km in altitude and traveling at 6.9 km/sec.

Plus+9 minutes, 20 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, 5 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, 30 seconds. Ariane is 201 km in altitude and traveling at 6.2 km/sec.

Plus+8 minutes. Coming up on main stage shutdown in about one minute. Velocity is 5.52 km/sec.

Plus+7 minutes, 30 seconds. Ariane is 199.9 km in altitude and traveling at 4.95 km/sec.

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

Plus+6 minutes, 30 seconds. Ariane is 193 km in altitude and traveling at 3.9 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, 30 seconds. Ariane is 178 km in altitude and traveling at 3.26 km/sec.

Plus+4 minutes, 35 seconds. Ariane is 157 km in altitude and traveling at 2.7 km/sec.

Plus+3 minutes, 45 seconds. Ariane remains right on course. The rocket is 131 km in altitude and traveling at 2.39 km/sec.

Plus+3 minutes, 15 seconds. Separation of the rocket's nose cone has been confirmed, uncovering the JCSAT 13 satellite in its upper position in the dual payload stack.

Plus+2 minutes, 45 seconds. The vehicle is 88 km in altitude, traveling at 2.1 km/sec.

Plus+2 minutes, 24 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+1 minute, 55 seconds. The vehicle is 43 km in altitude.

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 is 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 geosynchronous transfer orbit with the JCSAT 13 and the VINASAT 2 telecommunications satellites.

LIFTOFF! Liftoff of the Ariane 5 carrying spacecraft for Japan and Vietnam on a milestone mission for satellite-builder Lockheed Martin!

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 2206 GMT to govern the final seven minutes to launch.

Minus-20 minutes and counting. Today's mission represents the 62nd launch for the Ariane 5 rocket dating back to 1996 and the second this year. It is the 206th flight overall for the Ariane family of launchers since 1979.

What's more, it is the 27th Japanese spacecraft launched by Arianespace over the past 23 years since JCSAT 1 in 1989 and Vietnam's second satellite, both of which have been entrusted to Ariane 5.

As for satellite-building Lockheed Martin, tonight is the company's 100th and 101st commercial geostationary satellites to be launched. Arianespace has carried 41 of them in the past.

Welcome to our live launch coverage of Ariane 5 with the JCSAT 13 and VINASAT 2 payloads from the Guiana Space Center in Kourou, French Guiana on the northeastern coast of South America.

Launch time remains scheduled for 2213 GMT.

Check out this photo gallery of the Ariane 5 rocket poised on the launch pad!

Aiming for blastoff Tuesday carrying a pair of mirror-like "sister" satellites built in the U.S. by Lockheed Martin for telecommunications operators in Japan and Vietnam, a European Ariane 5 rocket was wheeled out to the launch pad today.

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

Tuesday's liftoff, unleashing 2.6 million pounds of thrust from its hydrogen-fueled main stage and twin solid rocket boosters, is scheduled for 6:13 p.m. EDT (2213 GMT). The day's available launch window extends 120 minutes.

Bound for a typical geosynchronous transfer orbit, the rocket will first deploy the JCSAT 13 spacecraft to provide direct-to-home television broadcasting for Japan's SKY Perfect JSAT Corporation and then release the VINASAT 2 satellite for Vietnam Posts and Telecommunications Group to relay TV, phone and radio signals.

The countdown clock will be started by Arianespace at 6:43 a.m. EDT and a complete check of electrical systems occurs at 10:43 a.m. EDT.

Fueling of the Ariane 5 with super-cold liquid hydrogen and liquid oxygen propellants begins at 1:23 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 2:23 p.m. EDT.

Chilldown conditioning of the Vulcain 2 first stage engine will occur at 2:53 p.m. EDT, and a communications check between the rocket and ground telemetry, tracking and command systems is scheduled for 5:03 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 25 seconds some 44 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, 54 seconds, followed moments later by stage separation and ignition of the hydrogen-fueled cryogenic HM7B upper stage engine all at altitude of 125 miles.

The rocket's upper stage will fire for nearly 16 minutes, accelerating to a velocity of 20,891 miles per hour to reach an elliptical orbit with an advertised high point of 22,314 miles, a low point of 155 miles and inclination of 2 degrees relative to the equator.

The release of JCSAT 13 is scheduled for T+plus 26 minutes, 35 seconds. The rocket's barrel-like Sylda 5 dual-payload adapter will be jettisoned 35 minutes into the flight to uncover the second passenger.

VINASAT 2 will separate from the lower portion of the payload stack at T+plus 36 minutes, 1 second, capping the ascent.

The satellites are the 100th and 101st commercial geostationary communications spacecraft built by Lockheed Martin. The history dates back to SATCOM 1 launched in December 1975.

The two birds going up on this launch are constructed around Lockheed Martin's A2100 satellite design. JCSAT 13, weighing 9,983 pounds at launch, is equipped with 44 Ku-band transponders for its TV broadcasting mission, slated to last at least 15 years. It will replace the aging JCSAT 4A, originally launched aboard an Atlas 2AS rocket from Cape Canaveral in February 1999, in coverage to Japan and Southeast Asia from an orbital position of 124 degrees East longitude.

VINASAT 2 is headed for an orbital slot of 131.8 degrees East longitude for its mission exceeding 15 years to broaden the telecommunications offerings of its operator in Vietnam and neighboring countries. The craft, weighing 6,546 pounds at launch, carries 24 Ku-band transponders. Vietnam Posts and Telecommunications Group deployed its first satellite, VINASAT 1, in April 2008.