BY SPACEFLIGHT NOW

Follow the preparations and launch of the Arianespace Ariane 4 rocket carrying the Spot 5 Earth-imaging satellite. Reload this page for the very latest on the mission.

SATURDAY, MAY 4, 2002

The French Spot 5 remote sensing satellite became the 200th payload to be launched by Arianespace Friday night, riding an Ariane 4 rocket into orbit around Earth's poles.
Read our full story.

0154 GMT (9:54 p.m. EDT Fri.)

Arianespace has confirmed tonight's launch successfully delivered Spot 5 into the proper orbit. This marks the 70th success in a row for the Ariane 4 rocket dating back to 1995.

We'll have a full wrap-up story and pictures a bit later this evening.

0151 GMT (9:51 p.m. EDT)

SPACECRAFT SEPARATION! The French Spot 5 Earth-imaging spacecraft has been released into space from the third stage, completing tonight's launch of the Ariane 4 rocket.

The spent third stage is carrying two small auxiliary payloads AMSAT-France, of the international amateur radio satellite organization. Remaining attached to the stage, the packages will be activated in about 10 days to transmit recorded voice messages and digital telemetry data for about 40 days.

0150 GMT (9:50 p.m. EDT)

Plus+19 minutes. Confirmation of third stage shut down, completing the powered phase of flight. Orbit has been achieved. Altitude is 810 km, velocity 7.54 km/sec.

0150 GMT (9:50 p.m. EDT)

Plus+18 minutes, 30 seconds. Altitude is 810.1 km, velocity 7.54 km/sec.

0149 GMT (9:49 p.m. EDT)

Plus+17 minutes, 30 seconds. About one minute remaining in the third stage burn. Altitude is 809.2 km, velocity 6.9 km/sec.

0148 GMT (9:48 p.m. EDT)

Plus+16 minutes, 35 seconds. Altitude 807 km, velocity 6.48 km/sec.

0147 GMT (9:47 p.m. EDT)

Plus+15 minutes, 30 seconds. Altitude 800 km, velocity 5.95 km/sec.

0146 GMT (9:46 p.m. EDT)

Plus+14 minutes, 20 seconds. Altitude 785 km, velocity 5.4 km/sec.

0145 GMT (9:45 p.m. EDT)

Plus+13 minutes, 30 seconds. The St. Hubert tracking station in Canada has aquired the rocket's signal as it travels northward to orbit.

0143 GMT (9:43 p.m. EDT)

Plus+12 minutes. Altitude 728 km, velocity 4.7 km/sec.

0142 GMT (9:42 p.m. EDT)

Plus+10 minutes, 30 seconds. Third stage burn continues. Altitude 665 km, velocity 4.34 km/sec.

0141 GMT (9:41 p.m. EDT)

Plus+9 minutes, 30 seconds. Altitude 611 km, velocity 4.16 km/sec.

0140 GMT (9:40 p.m. EDT)

Plus+8 minutes, 30 seconds. Altitude is 544 km, velocity 4.0 km/sec.

0139 GMT (9:39 p.m. EDT)

Plus+7 minutes, 30 seconds. System parameters are still reported normal. Altitude is 464 km, velocity 3.94 km/sec.

0138 GMT (9:38 p.m. EDT)

Plus+6 minutes, 30 seconds. Altitude is 370 km, velocity 3.9 km/sec.

0137 GMT (9:37 p.m. EDT)

Plus+5 minutes, 45 seconds. And the cryogenic upper stage has ignited for its lengthy burn to deliver the Spot 5 satellite payload into the desired Earth orbit.

0137 GMT (9:37 p.m. EDT)

Plus+5 minutes, 40 seconds. The second stage has burned out and separated.

0136 GMT (9:36 p.m. EDT)

Plus+5 minutes, 10 seconds. No problems reported by Arianespace thus far in the flight of the Ariane 4 rocket. Altitude is 223 km, velocity 3.5 km/sec.

0136 GMT (9:36 p.m. EDT)

Plus+4 minutes, 25 seconds. The payload fairing has been jettisoned since it is no longer needed to shield the Spot 5 spacecraft.

0135 GMT (9:35 p.m. EDT)

Plus+4 minutes. Altitude is 124 km, velocity 2.28 km/sec.

0135 GMT (9:35 p.m. EDT)

Plus+3 minutes, 45 seconds. The second stage has now ignited.

0135 GMT (9:35 p.m. EDT)

Plus+3 minutes, 35 seconds. The four first stage main engines have shut down and stage separation confirmed.

0134 GMT (9:34 p.m. EDT)

Plus+2 minutes, 30 seconds. The first stage main engines are still burning to continue the climb to orbit.

0133 GMT (9:33 p.m. EDT)

Plus+1 minute, 40 seconds. The two solid-propellant strap-on boosters have burned out and separated from the Ariane 4's first stage. The spent casings fall into the Atlantic Ocean. The first stage main engines and twin liquid-fueled strap-on motors are still burning to continue the climb to orbit.

0132 GMT (9:32 p.m. EDT)

Plus+1 minute. All parameters reported normal. The solid motors have burned out. Altitude 5.3 km, velocity 0.17 km/sec.

0132 GMT (9:32 p.m. EDT)

Plus+30 seconds. Ariane has pitched to the proper northward trajectory away from the launch site. The rocket is riding the thrust of six engines -- four liquid-fueled main engines and two solid-fueled strap-on boosters.

0131:46 GMT (9:31:46 p.m. EDT)

LIFTOFF! Liftoff of the Arianespace Ariane 4 rocket with the French Spot 5 Earth-imaging spacecraft. And the vehicle has cleared the tower!

0130:46 GMT (9:30:46 p.m. EDT)

Minus-1 minute. Equipment aboard the Ariane 42P 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.

0129:46 GMT (9:29:46 p.m. EDT)

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

0128:46 GMT (9:28:46 p.m. EDT)

Minus-3 minutes and counting.

0127:46 GMT (9:27:46 p.m. EDT)

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 Spot 5 spacecraft will be confirmed on internal power and declared ready for launch.

0125:46 GMT (9:25:46 p.m. EDT)

Minus-6 minutes and counting. The synchronized launch sequence has started. Computers are now in control of this final portion of the launch countdown. Liftoff is set for 0131:46 GMT.

During the next six minutes, the Ariane 42P 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. Ignition of the twin solid rocket boosters occurs at plus 4.2 seconds. Finally, the command will be issued to open the launch table clamps for liftoff between ignition +plus 4.4 and 4.6 seconds.

0124 GMT (9:24 p.m. EDT)

Minus-7 minutes. Standing by the handoff to the computer sequencer to complete the countdown tonight.

0120 GMT (9:20 p.m. EDT)

Minus-11 minutes and counting. The Ariane rocket will deliver the Spot 5 satellite into a Sun-synchronous orbit around Earth's poles. That means the rocket will head north from its launch pad, located on the northeast coast of South America. Here is a map of the trajectory to be followed tonight.

The target orbit is approximately 794 km on the low end and 812.7 km on the high end, with an inclination of 98.74 degrees. Ariane 4 is going for its 70th consecutive successful launch.

0116 GMT (9:16 p.m. EDT)

Minus-15 minutes. Arianespace reports there are no technical problems being worked and the countdown continues on schedule for liftoff as planned at 0131:46 GMT (9:31:46 p.m. EDT).

0111 GMT (9:11 p.m. EDT)

Minus-20 minutes and counting down to tonight's launch of the Ariane 42P rocket with the Spot 5 Earth-imaging spacecraft.

The three-stage rocket has been fully fueled and prepared for liftoff at 0131:46 GMT from the ELA-2 pad at the Guiana Space Center in South America.

Launch team members are watching systems on the Ariane 4 rocket, the spacecraft and ground support equipment. There are no problems being reported. The status panel in the Jupiter control center green across the board, indicating all systems are "go" at this time.

FRIDAY, MAY 3, 2002
2030 GMT (4:30 p.m. EDT)

Arianespace announced a short time ago it would provide a feed of the tonight's to the U.S. Public relations officials had said this week that a feed wouldn't be relayed to North America.

Those of you with satellite dishes, the broadcast will be available on GE-2, Transponder 3, Ku-band, downlink frequency 11760 V, starting 20 minutes before liftoff.

FRIDAY, MAY 3, 2002

A French Earth-imaging satellite is awaiting its launch into space Friday evening aboard an Ariane 4 rocket.

Liftoff of the Spot 5 satellite and the Ariane 42P rocket is set for the first of three precise instantaneous launch windows at 9:31:46 p.m. EDT (0131:46 GMT Saturday). Launch will take place from the ELA-2 launch pad in Kourou, French Guiana.

Due to budget cutbacks, Arianespace will not provide a live video broadcast of the launch to the U.S. As a result, we will be unable to provide our usual play-by-play coverage of the countdown and launch. Watch this page for a note confirming liftoff and another with news of spacecraft separation.

Friday night's launch will mark the 151st flight of an Ariane rocket, the 112th launch of an Ariane 4, and the 15th use of an Ariane 42P.

Flight 151's payload is the French Spot 5 satellite that will begin a five-year mission to observe Earth from space. The spacecraft was built by Astrium and weighs in at 6,666 pounds on the launch pad. It will be delivered into a circular Sun-synchronous orbit with an inclination of about 98 degrees and an altitude of around 813 kilometers.

Once in orbit, Spot 5 will join Spot 1, Spot 2 and Spot 4 in continuous observations of Earth's environment. Operated by the French CNES space agency, the Spot system has been providing users with high quality images on-demand since the first launch in 1986.

Spot 5 features several new imaging and data gathering instruments that were not included on previous Spot satellites. This new capability is expected to allow better data quality and variety.

Flight 151 also carries an amateur radio payload that will remain attached to the Ariane 4 third stage.

The latest preparations for Flight 151 have included the fueling of the Ariane 42P's first and second stages on Thursday with their load of unsymmetrical dimethyl hydrazine and nitrogen tetroxide.

Looking ahead to the key events Friday, the final countdown will commence at 1302 GMT (9:02 a.m. EDT). At 1957 GMT (3:57 p.m. EDT), the protective Ariane 4 service gantry will begin to be rolled back into its launch position. Super-cold liquid oxygen and liquid hydrogen will begin flowing into the cryogenic third stage at 2157 GMT (5:57 p.m. EDT). The launcher's telemetry, telecommand, and radar transponder systems will be switched on at 0027 GMT (8:27 p.m. EDT). Six minutes before launch, computers will take control of the countdown. Following this critical milestone is a series of fast-paced events that will culminate with the ignition of the first stage's Viking liquid-fueled engines. The solid-fueled strap-on boosters will ignite four seconds later, trailed immediately by liftoff.

The Ariane rocket will take a normal Ariane 42P ascent profile with a 90-second burn of the twin solid boosters. The first stage will shut down about three minutes, 30 seconds into the flight, then separate. The second stage will then come to life and burn for another two minutes, during which time the payload fairing will be jettisoned. The cryogenic third stage will then fire for a marathon 13-minute burn before shutting off and re-orienting for spacecraft separation, which will occur 19 minutes, 15 seconds after launch.

Come back to this page for confirmation of liftoff and spacecraft separation.

TUESDAY, APRIL 30, 2002

Arianespace will continue its fast-paced launch schedule for 2002 on Friday night when an Ariane 4 is set to loft a French Earth-imaging satellite into polar orbit.

Launch will occur from the ELA-2 launch pad at the Guiana Space Center in Kourou, French Guiana. Instead of a normal launch window, liftoff on Friday could happen at any of three instantaneous launch times. They are:

• 9:31:46 p.m. EDT (0131:46 GMT Saturday)
• 9:43:46 p.m. EDT (0143:46 GMT Saturday)
• 9:49:46 p.m. EDT (0149:46 GMT Saturday)

Flight 151's cargo is a French satellite named Spot 5, which will embark on a mission to image the Earth's surface, plus study climatic changes and the different processes that occur in our environment. The 6,666-pound Spot 5 will be the fifth launch of a Spot series spacecraft, all by an Ariane rocket.

Spot 5 will be placed into a Sun-synchronous orbit with an inclination of around 98 degrees, an orbit of choice for many science satellites.

Processing for Flight 151 began on February 21, when the Spot 5 payload arrived in Kourou from an assembly plant in Europe.

Ariane 4 launcher preparations got underway on April 8 with the placement of the first stage atop the launch table. The second stage joined the rocket on April 9, with third stage stacking on April 13.

Fueling of Spot 5 with its hazardous propellant commenced on April 17, beginning a several-day process.

The nearly-complete Ariane 42P was rolled out to the ELA-2 launch zone on April 22, followed two days later by the addition of the two solid-fueled strap-on boosters on April 24.

Spot 5 was enclosed inside the Ariane payload fairing last Thursday. The payload composite was taken to the pad on Friday, and the mating of the payload to the launcher occurred on Saturday, completing the assembly of the rocket.

A launch rehearsal occurred on Monday, giving the launch team a final chance to hone their skills before the real countdown on Friday.

Senior officials met on Tuesday to assess the readiness of the launch, and gvea final "go" for launch afterwards. Workers were to make ordnance connections later in the day.

On Thursday, the Ariane 4's first and second stages will be filled with their storable propellant combination of unsymmetrical dimethyl hydrazine and nitrogen tetroxide.

Stay with Spaceflight Now for continued updates and live play-by-play coverage of the countdown and launch Friday.