THURSDAY, SEPTEMBER 22, 2011
Generating an exhilarating wave of sound and light spreading miles around, an Ariane 5 rocket rose into space at sunset Wednesday with a communications satellite for the Middle East and another craft to serve commercial and U.S. government customers over North America.

Read our full story.

And see the launch photo gallery.

WEDNESDAY, SEPTEMBER 21, 2011
2220 GMT (6:20 p.m. EDT)
The next Ariane 5 launch is targeted for early March carrying the European Space Agency's third Automated Transfer Vehicle, named Edoardo Amaldi, to deliver supplies and equipment to the International Space Station.

Between now and then Arianespace will be focusing on the maiden flights of the Soyuz and Vega rockets from Kourou.

2216 GMT (6:16 p.m. EDT)
The Ariane 5 rocket has achieved its 46th consecutive successful launch since 2003 and the vehicle's 56th overall success in 60 flights since 1996.
2213 GMT (6:13 p.m. EDT)
Plus+35 minutes, 55 seconds. SPACECRAFT SEPARATION! The SES 2 communications satellite has been released from the Ariane 5 rocket's upper stage, completing today's launch.

SES 2 will join a constellation of 47 spacecraft operated by SES of Luxembourg. The system relays more than 5,900 television and radio channels to 250 million households across the world.

Orbital Sciences built SES 2 using its Star 2.4 model design. The 7,100-pound craft is equipped with 24 C-band and 24 Ku-Band transponders to broadcast television programming across North America and the Caribbean.

This new craft will be positioned in geostationary orbit at 87 degrees West to replace the aging AMC 3 that was launched by an Atlas 2A rocket from Cape Canaveral back in September 1997.

SES 2 also carries the U.S. Air Force's Commercially Hosted Infrared Payload, or CHIRP. The piggybacking device will test missile warning technologies from geosynchronous orbit.

2212 GMT (6:12 p.m. EDT)
Plus+34 minutes, 41 seconds. The barrel-like "Sylda" payload adapter between Arabsat 5C and the SES 2 satellites has been jettisoned. This has exposed SES 2 for its upcoming release from the rocket.
2211 GMT (6:11 p.m. EDT)
Plus+33 minutes, 30 seconds. Altitude is 2,220 km, velocity is 8.18 km/sec.
2210 GMT (6:10 p.m. EDT)
Plus+32 minutes, 30 seconds. Coming up on jettison of the rocket's dual payload adapter just over two minutes from now.
2209 GMT (6:09 p.m. EDT)
Plus+31 minutes, 30 seconds. Altitude is 1,775 km, velocity is 8.48 km/sec.
2208 GMT (6:08 p.m. EDT)
Plus+30 minutes, 15 seconds. Altitude is 1,515 km, velocity is 8.67 km/sec.
2206 GMT (6:06 p.m. EDT)
Plus+28 minutes, 45 seconds. Altitude is 1,224 km, velocity is 8.89 km/sec.
2205 GMT (6:05 p.m. EDT)
Plus+27 minutes, 24 seconds. SPACECRAFT SEPARATION! The Arabsat 5C telecommunications satellite has been released from the Ariane 5 rocket's upper stage.

Arabsat 5C carries 26 C-band transponders and 10 Ka-band spots for beaming video, voice, data and other services across Africa and the Middle East for operator Arabsat of Riyadh, Saudia Arabia. The 10,200-pound satellite was built by Astrium using the Eurostar E3000 design, while Thales Alenia Space provided the communications package for the spacecraft. It has a 15-year life expectancy.

This new craft will be positioned in geostationary orbit at 20 degrees East to replace the aging Arabsat 2B that was launched by an Ariane 4 rocket back in November 1996.

2204 GMT (6:04 p.m. EDT)
Plus+26 minutes, 15 seconds. Altitude is 807 km, velocity is 9.22 km/sec.
2203 GMT (6:03 p.m. EDT)
Plus+25 minutes, 5 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.
2202 GMT (6:02 p.m. EDT)
Plus+24 minutes. Altitude is 519 km, velocity is 9.2 km/sec.
2201 GMT (6:01 p.m. EDT)
Plus+23 minutes, 15 seconds. Less than two minutes of propulsion remains in the upper stage.
2200 GMT (6:00 p.m. EDT)
Plus+22 minutes. Altitude is 345 km, velocity is 8.89 km/sec.
2159 GMT (5:59 p.m. EDT)
Plus+21 minutes, 15 seconds. Altitude is 300 km, velocity is 8.76 km/sec.
2158 GMT (5:58 p.m. EDT)
Plus+20 minutes, 15 seconds. Just under five minutes remain in this firing of the upper stage.
2157 GMT (5:57 p.m. EDT)
Plus+19 minutes, 30 seconds. Altitude is 223 km, velocity is 8.49 km/sec.
2156 GMT (5:56 p.m. EDT)
Plus+18 minutes. Altitude is 185 km, velocity is 8.26 km/sec.
2155 GMT (5:55 p.m. EDT)
Plus+17 minutes. Altitude is 171 km, velocity is 8.09 km/sec.
2154 GMT (5:54 p.m. EDT)
Plus+16 minutes. The vehicle is on the upward climb again. Altitude is 164.7 km, velocity is 7.9 km/sec.
2153 GMT (5:53 p.m. EDT)
Plus+15 minutes, 30 seconds. Ariane is 163 km in altitude and traveling at 7.85 km/sec.
2152 GMT (5:52 p.m. EDT)
Plus+14 minutes, 15 seconds. Ariane is 163 km in altitude and traveling at 7.66 km/sec.
2150 GMT (5:50 p.m. EDT)
Plus+12 minutes, 55 seconds. Ariane is 169 km in altitude and traveling at 7.45 km/sec.
2150 GMT (5:50 p.m. EDT)
Plus+12 minutes, 15 seconds. Ariane is 173 km in altitude and traveling at 7.34 km/sec.
2149 GMT (5:49 p.m. EDT)
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.
2148 GMT (5:48 p.m. EDT)
Plus+10 minutes, 30 seconds. Ariane is 182 km in altitude and traveling at 7.1 km/sec.
2147 GMT (5:47 p.m. EDT)
Plus+9 minutes, 45 seconds. Ariane is 185 km in altitude and traveling at 7.0 km/sec.
2147 GMT (5:47 p.m. EDT)
Plus+9 minutes, 17 seconds. The upper stage of the Ariane 5 ECA rocket is up and burning to accelerate the payload into geosynchronous transfer orbit.
2147 GMT (5:47 p.m. EDT)
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 prior to completing an orbit of Earth.
2146 GMT (5:46 p.m. EDT)
Plus+8 minutes. Coming up on main stage shutdown in about one minute. Velocity is 5.5 km/sec.
2145 GMT (5:45 p.m. EDT)
Plus+7 minutes. The rocket's climb has leveled out as designed. This temporary trajectory is needed in order to gain speed.
2144 GMT (5:44 p.m. EDT)
Plus+6 minutes, 40 seconds. Ariane is 186 km in altitude and traveling at 4.2 km/sec.
2144 GMT (5:44 p.m. EDT)
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.
2143 GMT (5:43 p.m. EDT)
Plus+5 minutes, 30 seconds. Ariane is 174 km in altitude and traveling at 3.3 km/sec.
2142 GMT (5:42 p.m. EDT)
Plus+4 minutes, 30 seconds. Ariane is 154 km in altitude and traveling at 2.76 km/sec.
2141 GMT (5:41 p.m. EDT)
Plus+3 minutes, 45 seconds. Ariane remains right on course. The rocket is 132 km in altitude and traveling at 2.4 km/sec.
2141 GMT (5:41 p.m. EDT)
Plus+3 minutes, 15 seconds. Separation of the rocket's nose cone has been confirmed.
2140 GMT (5:40 p.m. EDT)
Plus+2 minutes, 55 seconds. The vehicle is 96 km in altitude.
2140 GMT (5:40 p.m. EDT)
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.
2139 GMT (5:39 p.m. EDT)
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.
2139 GMT (5:39 p.m. EDT)
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.
2138 GMT (5:38 p.m. EDT)
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 Arabsat 5C and the SES 2 broadcasting spacecraft to serve the Middle East and North America.
2138 GMT (5:38 p.m. EDT)
LIFTOFF! Liftoff of the Ariane 5 on a commercial trip to space with two communications satellites!
2137 GMT (5:37 p.m. EDT)
Minus-50 seconds. The vehicle is running on internal power.
2137 GMT (5:37 p.m. EDT)
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.
2136 GMT (5:36 p.m. EDT)
Minus-2 minutes. The Vulcain 2 main engine supply valves are being opened. And the ground valves for engine chilldown are being closed.
2135 GMT (5:35 p.m. EDT)
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.
2134 GMT (5:34 p.m. EDT)
Minus-4 minutes. Pressurization is now underway for the main stage's liquid oxygen and hydrogen tanks. Also, final pyrotechnic arming is starting.
2133 GMT (5:33 p.m. EDT)
Minus-5 minutes. Today marks the eighth time an Arabsat spacecraft has launched aboard an Ariane rocket and the 35th time the SES group.
2132 GMT (5:32 p.m. EDT)
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.
2131 GMT (5:31 p.m. EDT)
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.
2128 GMT (5:28 p.m. EDT)
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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2123 GMT (5:23 p.m. EDT)
Minus-15 minutes and counting. Today's mission represents the 60th launch for the Ariane 5 rocket dating back to 1996 and the fifth this year. It is the 204th flight overall for the Ariane family of launchers since 1979.
2118 GMT (5:18 p.m. EDT)
Minus-20 minutes and counting. No launch constraints are being reported with the Ariane rocket, its dual payload, ground systems or the weather. The Synchronized Sequence will assume control of the clock at 2131 GMT to govern the final seven minutes to launch.
2108 GMT (5:08 p.m. EDT)
Welcome to our live launch coverage for Ariane 5 with the Arabsat 5C and SES 2 payloads from the Guiana Space Center in Kourou, French Guiana on the northeastern coast of South America.

Launch time remains scheduled for 2138 GMT.

1910 GMT (3:10 p.m. EDT)
Arianespace reports all weather parameters are currently green. It is a warm, breezy day here in French Guiana with partly cloudy skies as fueling of the Ariane 5's cryogenic fuel tanks nears completion.
1845 GMT (2:45 p.m. EDT)
Check out the timeline of major events during tonight's launch.
1800 GMT (2:00 p.m. EDT)
All systems look good for launch so far in the countdown. Officials are keeping an eye on ground winds, but other weather conditions look acceptable for liftoff at 2138 GMT (5:38 p.m. EDT).
1605 GMT (12:05 p.m. EDT)
Arianespace picked up the countdown early this morning to preserve the chance for launch today. With the labor issue that thwarted yesterday's attempt now resolved, the countdown will continue this afternoon with fueling operations of the massive rocket's cryogenic core and upper stages.

Final countdown procedures began this morning around 1008 GMT (6:08 a.m. EDT). A check of electrical systems occurred around 1408 GMT (10:08 a.m. EDT).

Right now, workers are putting 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 1638 GMT (12:38 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 1738 GMT (1:38 p.m. EDT).

Chilldown conditioning of the Vulcain 2 first stage engine will occur at 1838 GMT (2:38 p.m. EDT), and a communications check between the rocket and ground telemetry, tracking and command systems is scheduled for 2028 GMT (4:28 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 21 seconds after liftoff.

Once above the dense atmosphere, the launcher's payload fairing will fall away at an altitude of nearly 70 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 22,236 miles and a targeted low point of 155 miles.

The release of Arabsat 5C is scheduled for 27 minutes, 21 seconds. The rocket's barrel-shaped Sylda 5 dual-payload adapter will be jettisoned a few minutes later.

SES 2 will separate from the lower portion of the payload stack at 35 minutes, 53 seconds.

1530 GMT (11:30 a.m. EDT)
COUNTDOWN UNDERWAY. Arianespace says it has resolved the labor dispute to permit another launch attempt tonight for the Ariane 5 rocket, the 204th Ariane mission since 1979.

Liftoff is scheduled for a window opening at 2138 GMT and closing at 2302 GMT (5:38-7:02 p.m. EDT).

1315 GMT (9:15 a.m. EDT)
Negotiations continue at this hour between CNES, the French space agency, and the Trade Union of French Guiana Workers.

The union, which is composed of workers from Telespazio France, went on strike yesterday and forced Arianespace officials to delay the launch of an Ariane 5 rocket here with two commercial telecommunications satellites.

Sources say the negotiations are making some progress, but the discussions have not reached a formal agreement yet.

Arianespace could wait to decide whether to attempt launch tonight until this afternoon when the Ariane 5 rocket's huge propellant tanks are to be filled with cryogenic fuel.

Launch preparations are continuing to preserve the opportunity to launch tonight if the labor issue is resolved.

TUESDAY, SEPTEMBER 20, 2011
Check out photos of the Ariane 5 rocket on the launch pad today and other views around the Guiana Space Center, Europe's gateway to space.
2355 GMT (7:55 p.m. EDT)
The rocket was healthy, the satellites were configured and the weather was picturesque, but an unexpected labor strike stood in the way of liftoff of an Ariane 5 launcher Tuesday with two payloads to serve the United States and the Middle East.

Read our full story.

1520 GMT (11:20 a.m. EDT)
The European Space Agency is reporting that Arianespace is delaying tonight's planned launch due to a strike.
1505 GMT (11:05 a.m. EDT)
The countdown clocks have stopped at the Ariane launch control center as an issue is apparently being worked. We'll bring you more details as we get them.
MONDAY, SEPTEMBER 19, 2011
Stephen Clark has filed this report from French Guiana.

One day before it's scheduled to leave the planet, a 16-story tall Ariane 5 rocket traversed a familiar 1.7-mile path from its final assembly building to the launch pad Monday.

It's supposed to be the last move on Earth for the hydrogen- and solid-fueled launch vehicle. The next time it's put into motion, 2.6 million pounds of thrust will be pushing all 780 metric tons of the rocket off the ground.

The one-hour ride along dual rail tracks seems like an unfitting prelude to the spectacle that's supposed to occur here in the Amazon jungle at 6:38 p.m. local time tomorrow (2138 GMT; 5:38 p.m. EDT).

It will take less than 36 minutes for the workhorse Ariane 5 rocket to release the Arabsat 5C and SES 2 communications satellites into an oval-shaped geosynchronous transfer orbit hugging the equator.

Like everything in the rocket business, things move slow until liftoff.

This launch was postponed from early September to give engineers time for supplementary checks on the Ariane 5 rocket's upper stage. Arianespace, the French company in charge of commercial Ariane rocket operations, says the launcher is good to go.

My charter flight from Washington touched down around 7:30 p.m. local time at the airport in Cayenne. Aboard the flight were executives from Arianespace, representatives of SES, the operator of one of the payloads on the launch, and officials from Orbital Sciences Corp., the builder of SES 2.

Tomorrow morning, we head to the Guiana Space Center in Kourou, the nerve center for European launch activities about 35 miles northwest of Cayenne.

It's my first time in French Guiana. This is one of the most sparsely-populated territories in all of South America, and it's on the northern fringe of the Amazon jungle. The climate is marked by high humidity, regular rain showers, and a consistent light breeze off the Atlantic Ocean.

France administers French Guiana as an overseas department. The region is perhaps most notable for its activities in spaceflight and the infamous Devil's Island penal colony. Both are on my list of places to see on this visit.

But our attention first turns toward tomorrow's launch. The opening of the launch window is just 11 minutes after sunset, potentially making for a colorful ascent into space.

If the timing is just right, the sun illuminates the solid rocket booster exhaust in a rainbow of colors, spanning from dark charcoal gray to white. In between is an intoxicating mix of red, orange, pink and purple.

The launch window extends until 8:02 local time (2302 GMT; 7:02 p.m. EDT) tomorrow.

The weather forecast looks favorable with mostly clear skies, light-to-moderate winds and warm temperatures.