BY JUSTIN RAY

January 10, 2001 -- Follow the preparations and launch of the Eurasiasat 1 communications satellite aboard an Arianespace Ariane 4 rocket. Reload this page for the very latest on the mission.

WEDNESDAY, JANUARY 10, 2001

A telecommunications satellite that will bridge 150 million Turkish-speaking people of Europe and Asia was launched into orbit Wednesday by an Arianespace Ariane 4 rocket, marking the European booster's 60th straight success. Read our full story.

2229 GMT (5:29 p.m. EST)

Plus+20 minutes, 30 seconds. SPACECRAFT SEPARATION! The Turkish Eurasiasat 1 telecommunications satellite has been released into space from the Ariane 4 rocket's third stage, completing tonight's successful launch of Arianespace Flight 137. This marks the remarkable 60th straight success for the Ariane 4 rocket dating back to 1995!

Check back a little later this evening for a full wrap-up story.

2229 GMT (5:29 p.m. EST)

Plus+20 minutes. Now seconds from payload separation.

2228 GMT (5:28 p.m. EST)

Plus+19 minutes, 30 seconds. The Libreville tracking station in Africa has acquired the rocket's signal. Altitude is 227 km, velocity 9.74 km/sec.

2228 GMT (5:28 p.m. EST)

Plus+19 minutes, 6 seconds. Third stage has shut down to complete the powered phase of flight. The stage will now provide the necessary pointing for deployment of the Eurasiasat 1 spacecraft in the next minute.

2227 GMT (5:27 p.m. EST)

Plus+18 minutes. Under a minute left in the third stage burn. Altitude is 181 km, velocity 9.14 km/sec.

2226 GMT (5:26 p.m. EST)

Plus+17 minutes, 30 seconds. The rocket has bottomed out in its sling-shot to orbit and is now climbing higher. Altitude is 175 km, velocity 8.86 km/sec.

2226 GMT (5:26 p.m. EST)

Plus+17 minutes. Altitude is 172 km, velocity 8.6 km/sec. The cryogenic third stage engine continues to fire.

2224 GMT (5:24 p.m. EST)

Plus+15 minutes, 30 seconds. About three minutes left in the third stage burn. Officials report all data coming from the rocket indicate systems are working as planned. Altitude is 181 km, velocity 7.8 km/sec.

2223 GMT (5:23 p.m. EST)

Plus+14 minutes, 40 seconds. The rocket has passed out of range of the Natal tracking station.

2223 GMT (5:23 p.m. EST)

Plus+14 minutes. The Ascension Island tracking station in the Atlantic Ocean has acquired the rocket's signal as it heads eastward away from South America. Altitude is 203 km, velocity 7.17 km/sec.

2221 GMT (5:21 p.m. EST)

Plus+12 minutes, 30 seconds. The Ariane rocket continues to gain speed. Altitude is 226 km, velocity 6.60 km/sec.

2220 GMT (5:20 p.m. EST)

Plus+11 minutes, 30 seconds. Altitude is 239 km, velocity 6.26 km/sec.

2219 GMT (5:19 p.m. EST)

Plus+10 minutes, 45 seconds. 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. Altitude is 245 km, velocity 6.03 km/sec.

2219 GMT (5:19 p.m. EST)

Plus+10 minutes. Altitude is 248.3 km, velocity 5.86 km/sec.

2218 GMT (5:18 p.m. EST)

Plus+9 minutes. All vehicle parameters reported normal. Altitude 244 km, velocity 5.54 km/sec.

2217 GMT (5:17 p.m. EST)

Plus+8 minutes. Third stage burn continues for the Ariane 4 rocket. Altitude 232 km, velocity 5.3 km/sec.

2216 GMT (5:16 p.m. EST)

Plus+7 minutes. The Natal tracking station in Brazil has picked up the rocket's signal as it travels downrange. Altitude is 208 km, velocity 5.11 km/sec.

2215 GMT (5:15 p.m. EST)

Plus+6 minutes, 30 seconds. A smooth flight of the Ariane 4 rocket continues. Absolutely no issues have been reported by Arianespace. Altitude is 192 km, velocity 5.0 km/sec.

2215 GMT (5:15 p.m. EST)

Plus+6 minutes. Burnout of the second stage has occurred and the spent stage has jettisoned. The cryogenic upper stage has now ignited for its long-duration burn to deliver the communications satellite payload into orbit. Vehicle remains on course and free of any reported problems.

2214 GMT (5:14 p.m. EST)

Plus+5 minutes, 30 seconds. Altitude is 149 km, velocity 4.6 km/sec.

2213 GMT (5:13 p.m. EST)

Plus+4 minutes, 30 seconds. The payload fairing has been jettisoned since it is no longer needed to shield the Eurasiasat 1 spacecraft. Altitude is 112 km, velocity 3.3 km/sec.

2212 GMT (5:12 p.m. EST)

Plus+3 minutes, 45 seconds. The four first stage main engines have shut down and stage separation confirmed. The second stage has now ignited. Altitude is 82.6 km, velocity 2.57 km/sec

2212 GMT (5:12 p.m. EST)

Plus+3 minutes, 10 seconds. First stage main engines continue to fire. Altitude is 58 km, velocity 1.98 km/sec.

2211 GMT (5:11 p.m. EST)

Plus+2 minutes, 10 seconds. The Ariane rocket continues on the proper course. No problems have been reported. Altitude is 31 km, velocity 0.75 km/sec.

2210 GMT (5:10 p.m. EST)

Plus+74 seconds. The four solid strap-on motors have been jettisoned from the Ariane 4 rocket's first stage. The spent casings are held for a half-minute to ensure they do not fall upon the Ariane 5 launch site.

2209 GMT (5:09 p.m. EST)

Plus+45 seconds. The solid rocket motors have burned out.

2209 GMT (5:09 p.m. EST)

Plus+30 seconds. Ariane is in the pitch maneuver to achieve the proper trajectory eastward away from the launch site. Main engines and four solid-fueled strap-on boosters are all firing to propel the vehicle away from its jungle launch site in South America.

2209 GMT (5:09 p.m. EST)

LIFTOFF! Liftoff of the Ariane 4 rocket with the Eurasiasat 1 satellite -- bridging telecommunications between Europe and Asia from space.

2208 GMT (5:08 p.m. EST)

Minus-1 minute. Equipment aboard the Ariane 44P rocket is being switched off ground-supplied power and 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.

2207 GMT (5:07 p.m. EST)

Minus-90 seconds and counting. The local tracking stations at the launch site have a firm lock on the rocket.

2207 GMT (5:07 p.m. EST)

Minus-2 minutes and counting. The third stage liquid oxygen tank has been pressurized for the launch.

2206 GMT (5:06 p.m. EST)

Minus-3 minutes and counting. Flight 137 will be the first of perhaps a dozen Ariane launches in 2001 and the 138th in the entire Ariane program. It will be the 102nd Ariane 4 mission and the 14th for the Ariane 44P version with four solid strap-on rocket boosters.

2205 GMT (5:05 p.m. EST)

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

In the next half-minute, the launch time will be loaded aboard the Ariane rocket's guidance system. Also, the Eurasiasat 1 spacecraft will be confirmed on internal power and declared ready for launch.

2204 GMT (5:04 p.m. EST)

Minus-5 minutes and counting.

2203 GMT (5:03 p.m. EST)

Minus-6 minutes. The synchronized launch sequence has started. Computers are now in control of this final segment of the launch countdown.

During the next six minutes, the Ariane 44P 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 between ignition +plus 4.1 and 4.6 seconds.

2202 GMT (5:02 p.m. EST)

Minus-6 minutes, 30 seconds. The computer-run synchronized sequence to govern the final countdown to launch will start in 30 seconds minute.

2202 GMT (5:02 p.m. EST)

Minus-7 minutes and counting. The countdown continues smoothly. Liftoff remains set to occur at 2209 GMT (5:09 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 minutes, 40 seconds into flight the Natal station in Brazil will pick up the rocket's signal as the third stage burn gets underway. At T+plus 13 minutes, 00 seconds the site on Ascension Island in the Atlantic Ocean will begin coverage. Libreville in Gabon will provide services beginning at T+plus 18 minutes, 10 seconds for spacecraft separation and the conclusion of Arianespace Flight 137.

2201 GMT (5:01 p.m. EST)

Minus-8 minutes and counting. Arianespace reports all systems are "go" for launch as scheduled today at 2209 GMT. The weather is acceptable, upper level winds are within limits and there are no technical problems being addressed.

2159 GMT (4:59 p.m. EST)

Minus-10 minutes and counting.

2150 GMT (4:50 p.m. EST)

An Ariane 4 rocket should be less than 20 minutes away from blastoff on Arianespace's first launch of 2001. We are awaiting the first countdown status update of the evening from Kourou, which is expected in a couple of minutes. Tonight's launch window opens at 2209 GMT.

1945 GMT (2:45 p.m. EST)

The countdown continues for today's planned launch of Arianespace Flight 137. But the skies are cloudy and there is rain in the area around the Guiana Space Center as seen in a video transmission from the launch site a short time ago. Gusty winds forced the launch to be postponed for the past two days.

1810 GMT (1:10 p.m. EST)

Arianespace has begun a new countdown for launch of the Eurasiasat 1 communications satellite aboard an Ariane 44P rocket. Officials report the winds have eased in Kourou, allowing for optimism of getting the rocket off the ground today during an available launch window of 2209 to 2353 GMT (5:09 to 6:53 p.m. EST).

The mobile service tower has been retracted from around the rocket and fueling of the third stage with super-cold liquid oxygen and liquid hydrogen will commence shortly.

We will have live coverage beginning in the final 20 minutes of the countdown and the entire flight of the Ariane 4, which is going for its 60th straight successful mission.

TUESDAY, JANUARY 9, 2001
1630 GMT (11:30 a.m. EST)

With winds at the Guiana Space Center persistently unacceptable today, Arianespace has decided to forego making a launch attempt tonight of the Ariane 4 rocket with Eurasiasat 1. The winds forced last night's attempt to be scrubbed, too.

Officials meeting in Kourou a earlier today concluded the winds had not abated enough to warrant fueling the rocket and counting down.

Weather balloons are used to measure the wind speed and direction. That data is then used to generate computer models to show where debris and wreckage would land should the rocket explode shortly after liftoff. The winds today would pose a threat because conditions are such that debris could be blown outside of preset safety areas.

The launch has been rescheduled for Wednesday during a window of 5:09 to 6:53 p.m. EST (2209-2353 GMT).

MONDAY, JANUARY 8, 2001

Gusty high altitude winds above the jungle launch site in Kourou, French Guiana forced Arianespace to scrub today's planned liftoff of an Ariane 4 rocket carrying the Eurasiasat 1 telecommunications satellite.

Weather balloons released periodically during the countdown indicated winds aloft were out of limits to permit the rocket to fly during the available launch window. The countdown was halted at T-minus 6 minutes while officials awaited another balloon to run its course before calling it a day.

"Looking at the data from the balloon, it was clear that wind conditions remained 'red' and the decision was made to postpone the launch for tonight," Jacques Rossignol, Arianespace's chief operating officer, said as he announced the postponement to guests in the control center.

The upper level winds, coupled with strong winds along the French Guiana coastline, posed safety threats that meant the launch needed to be delayed for at least 24 hours. Officials will again review the situation Tuesday, around six hours before liftoff time, to determine if conditions have improved sufficiently to warrant another launch attempt.

Tuesday's window extends from approximately 2208 to 2351 GMT (5:08-6:51 p.m. EST).

This launch -- Arianespace Flight 137 -- is already running a month behind schedule initially due to last-moment concerns with the rocket's nose cone and then by extra tests ordered on the Alcatel-built Eurasiasat 1 spacecraft.

Once the Ariane 4 does launch, it will be the first of as many as a dozen Arianespace missions in 2001.

2243 GMT (5:43 p.m. EST)

So it was a double scrub for tonight's two rocket launches. It was upper level winds to blame in the Ariane 4 postponement, but a much more dramatic countdown cutoff at T-minus 11 seconds for Sea Launch.

Arianespace is hoping to try again in 24 hours. Officials will decide at about 1600 GMT (11 a.m. EST) to determine whether to proceed with another attempt tomorrow night at roughly the same liftoff time of 2208 GMT.

2235 GMT (5:35 p.m. EST)

SCRUB! Arianespace reports tonight's launch attmept was been called off. Check back shortly for more information on rescheduling plans.

2210 GMT (5:10 p.m. EST)

The countdown remains holding at the Guiana Space Center where weather conditions aloft are causing problems tonight for Arianespace. The count is frozen at T-minus 6 minutes. Officials are not expecting the clock to resume before half-past the hour or so.

So with the delay, be sure to check out the latest news on Sea Launch and tonight's blastoff of a Zenit 3SL rocket, which is now 25 minutes away.

We will continue to update this page with Ariane 4 reports as information becomes available.

2202 GMT (5:02 p.m. EST)

Minus-6 minutes and holding. The countdown clock has been stopped. This unplanned hold is due to upper level winds that are out of tolerance above the launch site. Arianespace says the hold is estimated to last about 30 minutes. Tonight's available launch window extends to 2351 GMT (6:51 p.m. EST).

The count is halted at this specific point because once the clock passes Minus-6 minutes, the computer-controlled Synchronized Launch Sequence begins to ready the rocket and pad systems for flight. Once the sequence starts, it cannot be temporarily paused.

2159 GMT (4:59 p.m. EST)

Minus-9 minutes. It appears the upper level wind conditions are the problem tonight in Kourou. Weather balloons being released from the Guiana Space Center show the winds are unfavorable for the Ariane 4 to lift off at this time.

2158 GMT (4:58 p.m. EST)

Minus-10 minutes. Arianespace launch officials are currently discussing the status of the rocket, payload and weather conditions to determine readiness to continue with the countdown. Weather is currently "no go" on the status panel in the Jupiter control center at the Guiana Space Center.

2154 GMT (4:54 p.m. EST)

Minus-14 minutes. Still no word from Arianespace on exactly what is the weather constraint. However, the weather is currently "no go" for liftoff at this time. Should conditions remain unfavorable, the countdown clock will hold at T-minus 6 minutes prior to starting the Synchronized Launch Sequence. Tonight's window extends to 2351 GMT.

2153 GMT (4:53 p.m. EST)

Minus-15 minutes. The Ariane 44L rocket stands 54.4 meters tall and weighs 355 metric tons at liftoff. The Eurasiasat 1 spacecraft accounts for 3,535 kg (7,777 pounds) of that weight.

2151 GMT (4:51 p.m. EST)

It appears Arianespace's announcement today of a new launch time was erroneous. Liftoff is actually set for 2208 GMT (5:08 p.m. EST).

2151 GMT (4:51 p.m. EST)

Minus-17 minutes. Arianespace reports the weather conditions in French Guiana are currently "no go" for launch at this point. We are awaiting further details on what the problem is.

2146 GMT (4:46 p.m. EST)

The final minutes of the countdown are ticking away at the Guiana Space Center in South America where an Ariane 4 rocket sits fully fueled and prepped for blastoff on Arianespace's -- in fact planet Earth's -- first mission of 2001.

Launch team members are watching systems on the Ariane 4 rocket, Eurasiasat 1 spacecraft and ground support equipment. Everything is working as planned, officials say, for this evening's launch.

2136 GMT (4:36 p.m. EST)

Now inside a half-hour to the launch of Arianespace Flight 137. Our live coverage and countdown updates will begin in 10 minutes.

1930 GMT (2:30 p.m. EST)

The Arianespace Ariane 4 rocket has entered the final three hours of the countdown to launch today in French Guiana. There has been one change announced this afternoon. The available launch window has been tweaked, again. It now opens at 2206 GMT (5:06 p.m. EST) and extends to 2351 GMT (6:51 p.m. EST).

0501 GMT (12:01 a.m. EST)

If an Ariane 4 rocket launches on time Monday it will have the distinction as planet Earth's first space flight of 2001. And if the European launcher can deliver its Turkish communications satellite cargo into the correct orbit it will mark the workhorse Ariane 4's 60th consecutive success.

However, if the launch is postponed for more than 27 minutes, 30 seconds, Sea Launch's Zenit 3SL is poised to take the honor of the year's first liftoff.

The Ariane 4's launch window opens at 2208 GMT (5:08 p.m. EST) and closes at 2351 GMT (6:51 p.m. EST). Sea Launch's window opens at 2235:30 GMT (5:35:30 p.m. EST) and closes at 2313 GMT (6:13 p.m. EST). Thus, since the windows overlap, both launches do have a shot at having the historical tagged to them, but the Ariane 4 does get the first chance. Spaceflight Now will, of course, have full coverage of both launches.

The Arianespace Flight 137 launch was delayed for one month from early December when the builder of the Eurasiasat 1 payload -- Alcatel Space of France -- ordered more checks on the craft before they would clear it for launch.

The Ariane 4 will take the Eurasiasat 1 telecommunications satellite aloft for Eurasiasat, a company formed through cooperation between Turk Telecom and Alcatel Space, the prime manufacturer of the spacecraft. Through its 32 Ku-band transponders, Eurasiasat 1 can transmit and receive information to and from Turkey, Europe, central Asia, the Middle-East, Russia, India, and South Africa from its geostationary orbital slot at 42 degrees East over Somalia. It will be co-located at that position with the Turksat-1C communications satellite, which was launched aboard an Ariane 4 rocket in 1996.

Eurasiasat 1 will weigh 7,777 pounds at launch in around 17 hours. At the end of its 15-year mission, the spacecraft should have a mass of around 3,469 pounds. In orbit, the craft's solar arrays will span around 110 feet tip-to-tip.

Over the weekend, the rocket and payload were both cleared for flight on Saturday. On Sunday, the first and second stages of the Ariane 44P rocket were fueled with their storable liquid propellant, which is composed of a nitrogen tetroxide oxidizer and an unsymmetrical dimethyl hydrazine fuel.

Looking ahead, the final countdown will begin at 0738 GMT (2:38 a.m. EST). The service gantry will start retracting from its position around the rocket to its launch position at 1633 GMT (11:33 a.m. EST). Loading of the Ariane’s third stage with its cryogenic fuels will commence at 1833 GMT (1:33 p.m. EST). Controllers in the Jupiter launch control room will activate the launcher's telemetry, radar transponder, and telecommand systems at 2103 GMT (4:03 p.m. EST). At 2202 GMT (5:02 p.m. EST), if all reporting elements are "go," the synchronized launch sequence will begin. Following this critical milestone, a series of fast-paced events occur, culminating in the ignition of the first stage's four liquid-fueled engines. Following four seconds and later is the ignition of the four solid-fueled strap-on boosters, trailed immediately by liftoff.

The mission will take a normal Ariane 44P ascent profile with a one-minute burn of all four solids, a three-minute burn of the first stage, a two-minute burn of the second stage, and a thirteen-minute burn of the third stage.

Stay with Spaceflight Now throughout the final half-hour of the countdown and launch. We will provide live real-time play-by-play updates from T-30 minutes through spacecraft separation.

SATURDAY, JANUARY 6, 2001

Workers at the Arianespace launch base in South America have a busy weekend ahead of them as they ready an Ariane 4 rocket for launch Monday after a one-month delay to conduct extra inspections on the Eurasiasat 1 satellite cargo.

Flight 137 is set to take to the skies on its way to orbit from the Guiana Space Center's ELA-2 launch pad on Monday at 2208 GMT (5:08 p.m. EST). The launch window extends for 103 minutes. This is a slight change from an earlier launch window provided by Arianespace.

Since the now one-month delay of Flight 137 was announced in early December, the Ariane 44P's first and second stages were unloaded of their storable propellants on December 14, followed on December 15 by the removal of the communications satellite payload from the rocket. Eurasiasat 1 was then returned to one of the satellite processing facilities for checks of the craft to be conducted.

After nearly two weeks of tests and inspections, the spacecraft was once again placed inside the Ariane 4 protective payload fairing on December 28. Later the same day the entire payload unit was transferred back to the launch zone.

The payload was then re-attached to the third stage of the Ariane rocket on January 3. A full launch rehearsal was set to be performed on Friday, and Saturday will see the launch readiness review take place. If a final "go" is issued, the launcher will be armed for blastoff.

On Sunday, the first and second stages of the of the launch vehicle will be re-filled with their nitrogen tetroxide and unsymmetrical dimethyl hydrazine storable propellant combo.

The final countdown and the fueling of the third stage with its load of cryogenic fuels will occur on launch day -- Monday.

Stay with Spaceflight Now for continued updates throughout the final countdown and launch.

WEDNESDAY, JANUARY 3, 2001

Activity at Guiana Space Center's Ariane 4 launch pad is once again bustling as Arianespace has announced that Flight 137 is back on track for blastoff next week after a month-long delay caused by the rocket's Turkish communications satellite cargo.

The delay was ordered because Alcatel Space -- the manufacturer of the Eurasiasat 1 satellite -- ordered additional complementary checks of its craft. Specific details on the problem were never disclosed.

The new launch window opens on Monday, January 8, at 2218 GMT (5:18 p.m. EST) and closes at 0026 GMT (7:26 p.m. EST). The launch will occur using an Ariane 44P launch vehicle from ELA-2 at Guiana Space Center in Kourou, French Guiana.

Eurasiasat 1 will be operated by Monaco-based Eurasiasat, a jointly-owned venture between Turk Telecom and Alcatel. Once in orbit, the craft will be co-located at 42 degrees East along with Turksat-1C. After testing on Eurasiasat 1 is complete, its 32 Ku-band transponders will join Turksat-1C's in Eurasiasat's quest to build a communications link between Asia and Europe.

Flight 137 is going to be the 102nd flight of the venerable Ariane 4 rocket, and the 138th of the entire Ariane family since its inception. This launch is also expected to be the first of possibly 11 missions in 2001 for Arianespace, with five using the older Ariane 4 models and up to six using the newer Ariane 5 launcher.

MONDAY, DECEMBER 11, 2000

Engineers have ordered "additional verifications" to be performed on the Eurasiasat 1 satellite, delaying its launch aboard an Ariane 4 rocket that had been scheduled for tonight. Further details have not been released by Arianespace or satellite manufacturer Alcatel Space. A new launch date won't be set until "results of the satellite verification are known," Arianespace said in a statement.

1700 GMT (12:00 p.m. EST)

DELAY. Tonight's launch of the Ariane 4 rocket with the Eurasiasat 1 communications spacecraft has been postponed. We will have further details later today, plus Arianespace's plans for rescheduling the launch.

0501 GMT (12:01 a.m. EST)

A Turkish telecommunications satellite built to bridge Europe and Asia is poised for its launch into space later today atop an Arianespace Ariane 4 rocket.

Running three days behind schedule to allow time for technicians to remove and inspect the rocket's nose cone, liftoff of the 137th European Ariane vehicle is set for 2204 GMT (5:04 p.m. EST).

The Eurasiasat 1 telecommunications satellite will be operated by Monaco-based Eurasiasat, a company formed between Turk Telecom and Alcatel Space, the prime manufacturer of the spacecraft. Through its 32 Ku-band transponders, Eurasiasat 1 can transmit and receive information to and from Turkey, Europe, central Asia, the Middle-East, Russia, India, and South Africa from its geostationary orbital slot at 42 degrees East over Somalia. It will be co-located at that position with the Turksat-1C communications satellite, which was launched aboard an Ariane 4 rocket in 1996.

Eurasiasat 1 will weigh 7,777 pounds at launch. At the end of its 15-year mission, the spacecraft should have a mass of around 3,469 pounds. In orbit, the craft's solar arrays will span around 110 feet tip-to-tip.

Workers in Kourou finished final preparations for launch on Saturday and Sunday. Those preparations included the filling of the Ariane 44P's first and second stages with their storable propellant.

Looking ahead, the final countdown will begin at 0734 GMT (2:34 a.m. EST). The over 300-foot tall service gantry will start retracting from its position around the rocket to its launch position at 1629 GMT (11:29 a.m. EST). Loading of the Ariane's third stage with its cryogenic fuels will commence at 1829 GMT (1:29 p.m. EST). Controllers in the Jupiter launch control room will activate the launcher's telemetry, radar transponder, and telecommand systems at 2059 GMT (3:59 p.m. EST). At 2158 GMT (4:58 p.m. EST), if all reporting elements are "go," the synchronized launch sequence will begin. Following this critical milestone, a series of fast-paced events occur, culminating in the ignition of the first stage's four liquid-fueled engines. Following four seconds and later is the ignition of the four solid-fueled strap-on boosters, trailed immediately by liftoff.

The mission will take a normal Ariane 44P ascent profile with a one-minute burn of all four solids, a three-minute burn of the first stage, a two-minute burn of the second stage, and a thirteen-minute burn of the third stage.

Stay with Spaceflight Now for the launch this evening. We will provide live coverage here in our status center.

SATURDAY, DECEMBER 9, 2000

After a postponement to double-check the rocket's nose cone, Arianespace has rescheduled the flight of Ariane 4 launcher carrying the Eurasiasat 1 communications satellite for Monday evening from South America.

The Ariane 44P is due for blastoff at 2204 GMT (5:04 p.m. EST) from the ELA-2 pad at the Guiana Space Center in Kourou, French Guiana. The available launch window extends for two hours and nine minutes.

The rocket's protective nose cone, or payload fairing, was removed on Friday for inspections "after an anomaly was detected during the final pre-launch inspections on Wednesday," an Arianespace reported.

Now that the mission is cleared for launch, the storable propellant combination that fuels the Viking engines of the first and second stages of the Ariane 4 rocket will be loaded aboard the rocket Sunday, in advance of the final launch countdown and loading of the liquid hydrogen/liquid oxygen fuel combination that fuels the third stage's single HM-7B engine. The storable propellant combo is made up of unsymmetrical dimethyl hydrazine, the fuel, and nitrogen tetroxide, the oxidizer. The first stage features four Viking 5 engines and the second stage features one Viking 4 engine.

Stay tuned to Spaceflight Now for continued coverage of this mission and for live updates on launch day.

THURSDAY, DECEMBER 7, 2000

Arianespace has opted to delay its planned Friday launch of an Ariane 44P rocket with a Turkish communications satellite to allow "complementary checks" on the booster. Officials say the launch is off until at least early next week, although a firm date will not be announced until those checks are completed.

The postponement announcement came on Wednesday, the same day the final launch readiness review was scheduled. Reports from launch operations manager Daniel Groult as late as Tuesday had indicated that everything was proceeding as expected.

Arianespace's Flight 137 was poised to launch on December 8 from the ELA-2 launch pad at Europe's spaceport at Kourou, French Guiana.

When cleared for the launch, the Ariane 44P, which uses four solid-fueled strap-on boosters, will place the Eurasiasat 1 communications satellite into a geostationary transfer orbit.

Flight 137's Eurasiasat 1 satellite payload arrived in Kourou on October 20 to begin processing for this launch.

Preparations for the launch vehicle for Flight 137 began on November 9 when the first stage was lifted to the vertical position in the launcher integration building at ELA-2. The stage was then lowered onto its mobile launch table and bolted down. That action was followed later the same day by the stacking of the Ariane 4's second stage.

The third stage of the Ariane 44P launcher was lifted atop the second stage on November 10. The rocket's vehicle equipment bay was also put into place on the rocket on November 10. The VEB, which is located on top of the third stage, is commonly called the "brains" of the rocket because it contains most of the major systems involved in getting the launcher and payload to orbit, such as the command and control systems and the telemetry systems.

Flight 137's nearly complete Ariane 44P rocket was rolled the one kilometer from the launcher integration building on Saturday, November 25. The crucial milestone in the processing flow was followed on November 28 and 29 by the mating of the Ariane 44P's four solid-fueled strap-on boosters. Those boosters were put into place in pairs of two each day.

Working in parallel with operations at the pad, workers in the satellite processing facility enclosed the Eurasiasat 1 spacecraft inside its payload fairing on Tuesday, November 28. The payload unit, including the adapter, spacecraft, and fairing, was transferred to the ELA-2 launch pad on Wednesday. Thursday saw the mating and connections be performed between the Ariane rocket and the payload unit.

The launch rehearsal was successfully completed on Tuesday, before the stand-down was ordered. Once checks on the rocket are complete, workers will pick up where they left off -- with the fueling of the first and second stages with their storable propellant combination.

Eurasiasat 1 will be the first satellite placed into orbit for Eurasiasat, a company formed by a partnership between Turk Telecom and Alcatel Space. The Turkish company will use Eurasiasat's 32 Ku-band transponders to broadcast telecommunications services to Turkey, Europe, central Asia, the Middle East, Russia, India, and South Africa.

Stay with Spaceflight Now for more updates in the future regarding the launch campaign of Arianespace Flight 137.