BY SPACEFLIGHT NOW

Follow the launch of Arianespace's Ariane 5 rocket carrying the French Syracuse 3A military communications satellite and the U.S. Galaxy 15 cable television spacecraft. Reload this page for the latest on the mission.

2312 GMT (7:12 p.m. EDT)

Arianespace confirms today's launch has been successful. "We have two new birds around Earth," an Arianespace commentator says.

2309 GMT (7:09 p.m. EDT)

Plus+37 minutes, 12 seconds. SPACECRAFT SEPARATION! PanAmSat's commercial Galaxy 15 broadcast spacecraft to relay cable television across the U.S. has been released from the Ariane 5 rocket's upper stage, completing today's launch.

2307 GMT (7:07 p.m. EDT)

Plus+35 minutes. Deployment of Galaxy 15 is coming up in about two minutes.

2304 GMT (7:04 p.m. EDT)

Plus+32 minutes, 40 seconds. The barrel-like Sylda structure that has enclosed the Galaxy 15 satellite during launch was just jettisoned. Syracuse was mounted atop the Sylda, allowing Ariane 5 to carry two satellites on one launch.

2301 GMT (7:01 p.m. EDT)

Plus+29 minutes, 45 seconds. SPACECRAFT SEPARATION! The French Syracuse 3A military communications satellite has been released from the Ariane 5 rocket's upper stage.

2259 GMT (6:59 p.m. EDT)

Plus+27 minutes. The upper stage has shut down to complete powered flight for the launch. Standing by for deployment of the first payload.

2258 GMT (6:58 p.m. EDT)

Plus+26 minutes. Altitude has surpassed 1,400 km.

2255 GMT (6:55 p.m. EDT)

Plus+23 minutes. Altitude is 1,000 km, velocity is 8.4 km/sec.

2254 GMT (6:54 p.m. EDT)

Plus+22 minutes, 15 seconds. Altitude is 900 km.

2252 GMT (6:52 p.m. EDT)

Plus+20 minutes, 30 seconds. Ariane is now 700 km above Earth and still climbing with its dual-satellite payload.

2251 GMT (6:51 p.m. EDT)

Plus+19 minutes. Arianespace has not reported any problems during today's launch.

2249 GMT (6:49 p.m. EDT)

Plus+17 minutes. The upper stage has just under 10 minutes remaining in this firing.

2247 GMT (6:47 p.m. EDT)

Plus+15 minutes. Velocity has reached 8 km/sec.

2246 GMT (6:46 p.m. EDT)

Plus+14 minutes. Ariane 5 is passing an altitude of 300 km.

2243 GMT (6:43 p.m. EDT)

Plus+11 minutes. The vehicle is climbing again. Altitude is 177 km, velocity is 7.7 km/sec.

2242 GMT (6:42 p.m. EDT)

Plus+10 minutes, 15 seconds. The upper stage of Ariane 5G -- the storable propellant stage -- has ignited for its long-duration burn.

2242 GMT (6:42 p.m. EDT)

Plus+10 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 prior to completing an orbit of Earth.

2241 GMT (6:41 p.m. EDT)

Plus+9 minutes. Coming up on main stage shutdown in less than one minute. Altitude is 135 km, velocity is 6 km/sec.

2240 GMT (6:40 p.m. EDT)

Plus+8 minutes, 30 seconds. Velocity is 5.7 km/sec. The main stage engine continues to fire.

2239 GMT (6:39 p.m. EDT)

Plus+7 minutes. The rocket is flying through the portion of flight in which its trajectory levels out in order to gain speed.

2236 GMT (6:36 p.m. EDT)

Plus+4 minutes. Altitude is 131 km, velocity is 2.4 km/sec.

2235 GMT (6:35 p.m. EDT)

Plus+3 minutes, 30 seconds. Arianespace says the protective payload fairing enclosing the satellite has been separated from the Ariane 5.

2234 GMT (6:34 p.m. EDT)

Plus+2 minutes, 23 seconds. The solid rocket boosters have been jettisoned from the Ariane 5 rocket's core stage. The liquid-fueled Vulcain 1 main engine continues to fire to propel the vehicle and its satellite payload to space.

2233 GMT (6:33 p.m. EDT)

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

2233 GMT (6:33 p.m. EDT)

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

2232 GMT (6:32 p.m. EDT)

Plus+30 seconds. Rocket has completed its pitch and roll maneuvers as it heads eastward from the South American coast.

2232 GMT (6:32 p.m. EDT)

LIFTOFF! Liftoff of the Arianespace Ariane 5 rocket launching a pair of communications satellites!

2231 GMT (6:31 p.m. EDT)

Minus-40 seconds. The vehicle is switching to internal power.

2231 GMT (6:31 p.m. EDT)

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.

2230 GMT (6:30 p.m. EDT)

Minus-2 minutes. The Vulcain 1 main engine supply valves are being opened. Also, the ground valves for engine chilldown are being closed.

2229 GMT (6:29 p.m. EDT)

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.

2228 GMT (6:28 p.m. EDT)

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

2227 GMT (6:27 p.m. EDT)

Minus-5 minutes and counting. Status panels in the control center are green, indicating all systems are "go" for liftoff today.

The Synchronized Sequence is underway. 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.

2226 GMT (6:26 p.m. EDT)

The launch appears to be continuing on schedule, after some Arianespace broadcast problems tonight.

THURSDAY, OCTOBER 13, 2005

An Ariane 5 rocket is set for launch later today carrying the French Syracuse 3A military communications satellite and PanAmSat's commercial Galaxy 15 broadcast spacecraft to relay cable television across the U.S.

Liftoff from the jungle pad in Kourou, French Guiana, will be possible between 2232 and 2356 GMT (6:32-7:56 p.m. EDT).

This will be the third Ariane 5 of 2005.

The final countdown began this morning at the Launch-Minus 11 hour, 30 minute mark. That was followed by a check of electrical systems. Fueling of the first stage with its super-cold load of liquid hydrogen and liquid oxygen was set to commence in the final five hours before liftoff time.

The countdown will enter the synchronized launch sequence about seven minutes prior to launch. Next will be a fast-paced series of automated events transitioning the rocket and payload to internal power, pressurizing fuel tanks, and taking systems to flight mode. The Vulcain engine will come to life, followed by ignition of the solid rocket boosters and liftoff.

The twin boosters will burn for 2 minutes, 18 seconds, and the payload fairing will be released 3 minutes, 8 seconds after launch. The cryogenic first stage will exhaust its propellant resources almost 10 minutes into the flight. After separation, the storable propellant upper stage will ignite to begin its lengthy 17-minute burn to finish the Ariane 5's ascent.

Syracuse 3A deployment is set for 29 minutes, 28 seconds after liftoff, followed about 10 minutes later by release of Galaxy 15.

Watch this page for live updates during the launch.