BY JUSTIN RAY

December 22, 1999 -- Follow the launch of the Galaxy 11 communications satellite aboard an Ariane 4 rocket. Reload this page for the very latest on the mission.

0230 GMT (9:30 p.m. EST)

Arianespace has completed its launch campaign for 1999, completing 10 successful launches including the first commercial flight of the new Ariane 5 rocket.

An Ariane 44L rocket lifted off right on schedule today at 0050 GMT (7:50 p.m. EST Tuesday) with the Galaxy 11 communications satellite from ELA-2 in Kourou, French Guiana.

"Well I think that was a very nice way to finish the year," Jacques Rossignol, Arianespace's chief operating officer told the crowd gathered in Kourou following tonight's successful launch.

See our Flight 125 photo gallery for images of the launch campign and mission.

The year got off to a slow start with only two launches in the year's first half because of delays in delivery of payloads. But Arianespace roared back and conducted a string of eight successful flights since August, including three since December 3.

"We decided to set a very ambitious goal to satisfy the need of almost all of our customers. We decided we needed to launch eight satellites in five months, which represents the equivalent of 20 launches a year," Rossignol said.

Arianespace Flight 125, carried out just two days before the 20th anniversary of the first Ariane launch, placed the Galaxy 11 communications satellite into space for builder Hughes and operator PanAmSat.

"You could not ask for a better Christmas present," said Douglas Kahn, PanAmSat's president and chief executive officer.

Contact with the satellite was successfully established at 0145 GMT (8:45 p.m. EST) through a ground station in Sydney, Australia.

Controllers are making plans to begin 90 days worth of maneuvers to raise the craft's altitude from its currently elliptical transfer orbit to a geostationary position 22,300 miles above Earth. The maneuvers will be completed by the satellite's xenon ion propulsion system called XIPS, Hughes spokeswoman Fran Slimmer said.

Later, testing and checkouts will be conducted on the satellite's communications payload and subsystems before Galaxy 11 becomes operational.

Galaxy 11 is the first in a new series of satellites - Hughes' HS702 design. Galaxy 11 has become the most powerful commercial communications satellite ever launched. It features 64 transponders and will be used for television broadcasting and other telecommunications services to North America and Brazil from its orbital slot of 99 degrees West.

The new craft is the first of seven PanAmSat plans to launch over the next 18 months. Jubilant PanAmSat officials in Kourou quickly removed outer shirts to reveal T-shirts that read "The Momentum is Growing" after the spacecraft separated from the Ariane rocket.

Officials are already looking ahead to the next Arianespace launch, which will carry PanAmSat's Galaxy 10R spacecraft into orbit. The satellite will replace the one lost aboard the Delta 3 failure in August 1998. Galaxy 10R is slated to arrive in Kourou on December 28 for launch by January 24.

This will conclude our live coverage of Arianespace Flight 125 and launch of Galaxy 11.

0111 GMT (8:11 p.m. EST)

Plus 21 minutes, 30 seconds. SPACECRAFT SEPARATION! The Galaxy 11 communications satellite has successfully separated from the Ariane 4 rocket's third stage. The satellite will make its first contact with ground controllers in the next 20 minutes.

We will have a wrap-up of this launch with quotes from officials a bit later tonight.

0110 GMT (8:10 p.m. EST)

Plus 20 minutes. Spacecraft separation is expected about 21 minutes, 21 seconds into flight. Altitude 396 km, velocity 9.6 km/sec.

0109 GMT (8:09 p.m. EST)

Plus 19 minutes, 10 seconds. Third stage has finished its burn after consuming all its propellant, completing the powered flight for this launch. Altitude 324 km, velocity 9.7 km/sec.

0108 GMT (8:08 p.m. EST)

Plus 18 minutes. Coming up on cutoff of the third stage in less than a minute.

0107 GMT (8:07 p.m. EST)

Plus 17 minutes, 30 seconds. The Libreville tracking station in Gabon has acquired the rocket's signal as it continues heading across the Atlantic from South America.

0107 GMT (8:07 p.m. EST)

Plus 17 minutes. Altitude 244 km, velocity 8.8 km/sec.

0106 GMT (8:06 p.m. EST)

Plus 16 minutes. Less than three minutes left in the third stage burn. Ariane begin to climb back in altitude. Altitude 229 km, velocity 8.3 km/sec.

0104 GMT (8:04 p.m. EST)

Plus 14 minutes, 30 seconds. Altitude 224 km, velocity 7.79 km/sec.

0102 GMT (8:02 p.m. EST)

Plus 12 minutes, 45 seconds. Altitude 232 km, velocity 7.1 km/sec.

0102 GMT (8:02 p.m. EST)

Plus 12 minutes. Acsension Island in the Atlantic Ocean has picked up the rocket. The long-duration burn of the third stage continues.

0101 GMT (8:01 p.m. EST)

Plus 11 minutes. Now reaching the period in flight where the Ariane rocket gives up a bit of altitude in order to gain velocity like a sling-shot.

0100 GMT (8:00 p.m. EST)

Plus 10 minutes. Altitude 241 km, velocity 6.35 km/sec.

0059 GMT (7:59 p.m. EST)

Plus 9 minutes. Ariane rocket continues right down the proper trajectory. All systems are operating normally.

0057 GMT (7:57 p.m. EST)

Plus 7 minutes, 30 seconds. Altitude 215 km, velocity 5.7 km/sec.

0056 GMT (7:56 p.m. EST)

Plus 6 minutes, 45 seconds. The Natal tracking station in Brazil has acquired the rocket.

0056 GMT (7:56 p.m. EST)

Plus 6 minutes. The second stage has completed its burn and separated. Third stage ignition confirmed.

0055 GMT (7:55 p.m. EST)

Plus 5 minutes. Altitude 138 km, velocity 4.4 km/sec.

0054 GMT (7:54 p.m. EST)

Plus 4 minutes. Second stage has ignited and the payload fairing has separated. All data looks good from the rocket.

0053 GMT (7:53 p.m. EST)

Plus 3 minutes, 45 seconds. Four first stage Snecma Viking 5 engines are have cutoff and the first stage has separated to fall into the Atlantic.

0052 GMT (7:52 p.m. EST)

Plus 2 minutes, 30 seconds. The liquid-propellant boosters have separated.

0051 GMT (7:51 p.m. EST)

Plus 90 seconds. Altitude 12.7 km, velocity 0.47 km/sec.

0051 GMT (7:51 p.m. EST)

Plus 1 minute. All systems reported normal.

0050 GMT (7:50 p.m. EST)

LIFTOFF! Liftoff of the Ariane 4 rocket launching a new era in communications satellite technology with the first Hughes HS702 spacecraft - PanAmSat's powerhouse Galaxy 11.

0049 GMT (7:49 p.m. EST)

Minus 1 minute. Equipment aboard the Ariane 44L rocket is being switched to onboard batteries for launch.

In the final seconds of the countdown, activities will include releasing the inertial platform at minus 9 seconds, and the release command to the retraction system for the two cryogenic arms will be given at minus 5 seconds.

0048 GMT (7:48 p.m. EST)

Minus 2 minutes. Today's launch will be the 125th for an Ariane rocket, the 10th of 1999, the 93rd Ariane 4 to be flown and the 29th for an Ariane 44L configuration vehicle with four strap-on liquid propellant boosters.

0046 GMT (7:46 p.m. EST)

Minus 3 minutes, 30 seconds. The launch time has been loaded aboard the Ariane rocket's guidance system. Also, the Galaxy 11 spacecraft is reported to be running on internal power and ready for launch.

0046 GMT (7:46 p.m. EST)

Minus 4 minutes and counting. The launch team is watching over the final topping off of liquid oxygen and liquid hydrogen supplies aboard the rocket's third stage.

0044 GMT (7:44 p.m. EST)

Minus 6 minutes. Arianespace has given the go for synchronized launch sequence start. Computers are now in control of this final segment of the launch countdown. The launch time is targeted for 0050 GMT (7:50 p.m. EST).

During the last six minutes, the Ariane 44L rocket, satellite payload and ground systems will be configured for launch. There are two master computers running the countdown. One is responsible for fluids and propellants and the other for final preparation of the electrical systems such as initiating the flight program, activation of the engine steering systems and power transfer from ground supplies to onboard batteries. The computers will control until minus 5 seconds when a majority logic sequencer takes over for first stage engine start at zero seconds. Engine performance checks are done in parallel by the two computers starting at plus 2.8 seconds. Finally, the command will be issued to open the launch table clamps for liftoff.

0040 GMT (7:40 p.m. EST)

Minus 10 minutes. There are no problems to report in the countdown. Liftoff remains set to occur at 0050 GMT (7:50 p.m. EST).

A network of tracking stations are standing ready to relay data from the Ariane 4 rocket to engineers in Kourou. The early portion of flight will be monitored through the Kourou and Cayenne stations in French Guiana. About 6 1/2 minutes into flight the Natal station in Brazil will pick up the rocket's signal as the third stage burn gets under way. At plus 12 minutes, the site on Ascension Island in the Atlantic Ocean will begin coverage. Libreville and Gabon will provide services for spacecraft separation and the conclusion of Arianespace Flight 125.

0035 GMT (7:35 p.m. EST)

Minus 15 minutes and counting. Tonight's launch will be the 14th time PanAmSat has used an Arianespace rocket to place its communications satellites into space. Earlier spacecraft launched by Ariane rockets are PAS 1, 2, 3, 4, 6, 6B, 3R and 7, Galaxy 4, 6 and 7, and SBS 5 and 6.

0030 GMT (7:30 p.m. EST)

Minus 20 minutes and counting. The countdown remains on schedule for liftoff at 0050 GMT (7:50 p.m. EST). The rocket, spacecraft and weather are go for launch.

This will be the third Ariane launch in 18 days. An Ariane 4 successfully launched a pair of reconnaissance satellites for the French Ministry of Defence on December 3 and the first commercial flight of the Ariane 5 rocket carried the European Space Agency's X-ray Multi-Mirror telescope into Earth orbit on December 10.

0025 GMT (7:25 p.m. EST)

Minus 25 minutes and counting. Friday will mark the 20th anniversary of the first Ariane launch. Since 1979, 124 Ariane rockets have been flown.

0015 GMT (7:15 p.m. EST)

Minus 35 minutes and counting. The cargo to be launched into space tonight aboard the Ariane 4 rocket is the U.S. telecommunications satellite Galaxy 11 for PanAmSat.

Simply put, Galaxy 11 is 4 1/2-tons of pure broadcasting power. The spacecraft is the first Hughes Space and Communications-built HS702 model satellite, and will become the most powerful commercial communications satellite ever launched.

Galaxy 11 currently weighs 9,900 pounds on the launch pad. It carries 40 Ku-band and 24 C-band transponders and will have 10 kilowatts of power at the end of its 15-year life. The craft will be positioned at 99 degrees West to provide television broadcasting, Internet and other telecommunications services throughout North America.

Accoring to Hughes, the HS702 design offers satellite operators a giant in size, performance and cost efficiency. Hughes introduced the model in October 1995, as an evolution of its popular and successful HS 601 and HS 601HP satellites. The body-stabilized HS702 can deliver payloads exceeding 90 active transponders, in any communications frequencies that customers request. Power levels start at 10 kilowatts and climb to 15 kilowatts in the "max power" configuration. The spacecraft is adaptable to medium and geosynchronous earth orbits.

The HS702 also carries the advanced xenon ion propulsion system for attitude control in space. A new feature is angled reflector panels along both sides of the solar wings, forming a shallow trough to focus the sun's rays on the solar cells. These high-efficiency, dual-junction gallium arsenide cells supply twice the power of traditional silicon cells.

Read about Galaxy 11's planned uses from PanAmSat and about the first HS702 satellite from Hughes.

0000 GMT (7:00 p.m. EST)

Minus 50 minutes and counting. The status panel in the Jupiter control center is green across the board with no problems to report tonight.

TUESDAY, DECEMBER 21, 1999
2340 GMT (6:40 p.m. EST)

The countdown for launch of Arianespace Flight 125 is nearing the final stages in Kourou, French Guiana along South America's northeastern coastline. Liftoff from the ELA-2 launch complex is planned for 7:50 p.m. EST (0050 GMT). No problems are being reported and clocks are ticking down on schedule.

0501 GMT (0001 EST)

The third Arianespace launch of December is less than 24 hours away. An Ariane 44L rocket, the most powerful of the Ariane 4 family with four liquid-fuel strap-on boosters, will carry PanAmSat's Galaxy 11 communications satellite into Earth orbit. Liftoff from Kourou in French Guiana is planned for 7:50 p.m. EST Tuesday (0050 GMT Wednesday), the opening of a 30-minute window.

Arianespace cleared the rocket for flight on Saturday during the launch readiness review. That allowed for the rocket to be armed that day and fueling of the first and second stages with storable propellant on Monday.

The final countdown will begin today at 1020 GMT (5:20 a.m. EST). The 321-foot tall gantry enclosing the rocket at the ELA-2 launch complex will be retracted beginning at 1855 GMT (1:55 p.m. EST). Loading of super-cold liquid oxygen and liquid hydrogen into the Ariane's third stage will commence at 2115 GMT (4:15 p.m. EST). The launch team will activate the rocket's telemetry, radar transponders and telecommand systems just over an hour before launch at 2345 GMT (6:45 p.m. EST). If there are no problems standing in the way of an on-time launch, officials will allow the Synchronized Launch Sequence to begin at Launch Minus-6 minutes. This computer-controlled process performs the final tasks to prepate the rocket for launch.

Galaxy 11 will become the most powerful commercial communications satellite ever launched. It is the first of a new generation of satellites - the HS702 - built by Hughes Space and Communications. The 9,900-pound craft features 64 transponders, 40 in Ku-band and 24 in C-band. Galaxy 11 will be positioned in geostationary orbit 22,300 miles above the Earth's equator at 99 degrees West longitude. The satellite will cover North America and Brazil, relaying television, voice and data transmissions.

"The launch of Galaxy 11 is a major event for PanAmSat and Hughes as well as the entire satellite communications industry, as we deploy this powerful new satellite," said R. Douglas Kahn, PanAmSat's president and chief executive officer.

Galaxy 11 is the first of seven new PanAmSat satellites to be launched over the next 18 months.