2133 GMT (5:33 p.m. EDT)
"That was a fantastic launch!" says Sea Launch President Kjell Karlsen. "Sea Launch is back."
2132 GMT (5:32 p.m. EDT)
Controllers have established contact with the Atlantic Bird 7 spacecraft via a ground tracking station following today's launch into orbit.
2125 GMT (5:25 p.m. EDT)
T+plus 67 minutes, 25 seconds. SPACECRAFT SEPARATION! The Atlantic Bird 7 communications spacecraft has been released from the Block DM-SL upper stage to complete this first Sea Launch flight in two-and-a-half years.

Satellite operator Eutelsat of Paris will use the commercial Atlantic Bird 7 in geostationary orbit at its 7-degree West longitude location to provide digital broadcasting and Internet services across the Middle East and Africa.

The company's Hot Bird 10 satellite, launched in February 2009, has been temporarily parked in that slot for the past two years while waiting for Atlantic Bird 7 to get built and launched. Once the new bird arrives on station, Hot Bird 10 will be freed to move elsewhere and join Eutelsat's direct-to-home TV satellite group.

Atlantic Bird 7 was built by EADS Astrium using the Eurostar E3000 platform. The 10,200-pound craft is equipped with a communications payload consisting solely of Ku-Band transponders, a pair of power-generating solar wings spanning 108 feet and a life expectancy of 15 years.

The satellite will be co-located with three Egyptian-owned Nilesat spacecraft to enhance the communications capabilities over the coverage zone. Eutelsat says currently over 450 television channels are relayed from that orbital vantage point to reach 38 million homes.

As many as 44 of Atlantic Bird 7's transponders will form a high-power footprint over the Middle East and North Africa for direct-to-Home TV broadcasting.

A second footprint using up to 12 transponders will give Internet access for northwestern Africa.

Ground controllers will spend the next 9 days maneuvering Atlantic Bird into its circular geostationary orbit. Deployment of the craft's appendages and testing will follow before the satellite goes operational in about a month.

2120 GMT (5:20 p.m. EDT)
T+plus 62 minutes. Deployment of the spacecraft from the upper stage is just over five minutes away as the rocket flies above the Indian Ocean.

During this coast period between completion of the Block DM-SL stage's burn and spacecraft separation, the stage is providing the necessary control and orientation for payload release.

2115 GMT (5:15 p.m. EDT)
T+plus 57 minutes, 32 seconds. The Block DM-SL's 11D58M main engine has shut down, completing the powered phase of today's launch. The stage will now coast for approximately 10 minutes before deploying the Atlantic Bird 7 satellite.
2114 GMT (5:14 p.m. EDT)
T+plus 56 minutes, 30 seconds. Engine pressures reported normal as the upper stage continues firing. Just over a minute left to go in this burn.
2112 GMT (5:12 p.m. EDT)
T+plus 54 minutes. The rocket is soaring high above Africa during this engine firing.
2110 GMT (5:10 p.m. EDT)
T+plus 52 minutes. The Block DM-SL is stable as this six-minute burn gets underway.
2109 GMT (5:09 p.m. EDT)
T+plus 51 minutes, 41 seconds. Ignition! The upper stage has reignited to send Atlantic Bird 7 into geosynchronous transfer orbit.
2057 GMT (4:57 p.m. EDT)
T+plus 39 minutes. The vehicle is about 370 miles above the Atlantic Ocean.
2049 GMT (4:49 p.m. EDT)
T+plus 31 minutes. Twenty minutes from engine restart. The rocket is coasting over South America.
2038 GMT (4:38 p.m. EDT)
T+plus 20 minutes. The upper stage will coast in this orbit until the Block DM-SL reignites at T+plus 51 minutes, 31 seconds for the firing to achieve geosynchronous transfer orbit. The burn should last about six minutes. Deployment of Atlantic Bird 7 to complete today's launch is expected about 67 minutes after liftoff.
2032 GMT (4:32 p.m. EDT)
T+plus 14 minutes, 30 seconds. Engine cutoff. The Block DM-SL upper stage has completed its first burn, injecting the motor and attached Atlantic Bird 7 spacecraft into a temporary parking orbit around Earth.
2031 GMT (4:31 p.m. EDT)
T+plus 13 minutes, 50 seconds. The vehicle has reached orbital velocity. Less than a minute remains in this planned upper stage burn to reach an elliptical parking orbit with a low point of 112 miles and a high point of 1,153 miles.
2030 GMT (4:30 p.m. EDT)
T+plus 12 minutes, 45 seconds. Everything continues to look good.
2030 GMT (4:30 p.m. EDT)
T+plus 12 minutes. The Block DM-SL main engine is burning a mixture of highly refined kerosene propellant and supercold liquid oxygen.
2028 GMT (4:28 p.m. EDT)
T+plus 10 minutes. The Block DM-SL is stable and firing normally. This burn of the upper stage will last just under six minutes.
2026 GMT (4:26 p.m. EDT)
T+plus 8 minutes, 54 seconds. The Block DM-SL upper stage has ignited for today's first of two firings to propel the Atlantic Bird 7 spacecraft from the current suborbital trajectory to geosynchronous transfer orbit.
2026 GMT (4:26 p.m. EDT)
T+plus 8 minutes, 38 seconds. The second stage vernier engines have shut down and jettisoning of the spent stage has occurred.
2026 GMT (4:26 p.m. EDT)
T+plus 8 minutes. Venier engine pressures are normal.
2025 GMT (4:25 p.m. EDT)
T+plus 7 minutes, 10 seconds. The second stage RD-120 main engine has shut down. The vernier steering engines are still burning as designed.
2025 GMT (4:25 p.m. EDT)
T+plus 7 minutes. The second stage is throttling down in preparation for engine cutoff.
2024 GMT (4:24 p.m. EDT)
T+plus 6 minutes, 30 seconds. Second stage engine performance is normal as the motor continues to fire.
2024 GMT (4:24 p.m. EDT)
T+plus 6 minutes. NASA's Tracking and Data Relay Satellite System has acquired the vehicle's signal to receive telemetry for transmission to Sea Launch ground engineers. The second stage is still firing.
2023 GMT (4:23 p.m. EDT)
T+plus 5 minutes, 30 seconds. Flight remains normal for the Sea Launch rocket following today's liftoff at 2018 GMT. The second stage engine continues to burn.
2022 GMT (4:22 p.m. EDT)
T+plus 4 minutes, 30 seconds. The rocket remains stable on the second stage propulsion.
2021 GMT (4:21 p.m. EDT)
T+plus 3 minutes, 15 seconds. The rocket's payload fairing, or nose cone, has been jettisoned. It protected the satellite cargo during atmospheric ascent.
2020 GMT (4:20 p.m. EDT)
T+plus 2 minutes, 45 seconds. The second stage engine has been ignited for its firing.
2020 GMT (4:20 p.m. EDT)
T+plus 2 minutes, 35 seconds. The first stage RD-171 engine has shut down and the spent stage was jettisoned.
2019 GMT (4:19 p.m. EDT)
T+plus 1 minute, 10 seconds. The vehicle has passed through the region of maximum dynamic pressure.
2018 GMT (4:18 p.m. EDT)
T+plus 30 seconds. The 20-story rocket is riding the thrust of the first stage main engine as it powers into the equatorial skies. The Russian-made engine has four nozzles and propels the rocket for the first two-and-a-half minutes of flight.
2018 GMT (4:18 p.m. EDT)
LIFTOFF! Liftoff of the Sea Launch Zenit 3SL rocket, the booster of commercial communications satellites returns to action!
2017 GMT (4:17 p.m. EDT)
T-minus 1 minute. The rocket stands pressurized and ready for blastoff as the automatic launch sequence enters the final 60 seconds.
2012 GMT (4:12 p.m. EDT)
Unfortunately, Sea Launch has encountered a problem with its live Internet broadcast of today's liftoff. We'll pass along further details about the flight's progress as it becomes available.
2006 GMT (4:06 p.m. EDT)
T-minus 12 minutes and counting. The transporter/erector arm has pulled away from the Sea Launch Zenit 3SL rocket. The arm was used to roll the rocket out of the environmentally-controlled hangar atop the Odyssey platform and lift the rocket upright yesterday.

The arm is being lowered to the platform deck where it will be returned to the hangar and the doors closed for launch.

Fueling operations have been completed aboard the Odyssey platform. Over the past couple of hours, the rocket was loaded with kerosene propellant and cryogenic liquid oxygen. The platform was cleared of all workers prior to this hazardous activity, with all personnel moved to the Sea Launch Commander ship safely positioned about three miles uprange.

2005 GMT (4:05 p.m. EDT)
Still waiting for Sea Launch's live mission coverage to start.
1930 GMT (3:30 p.m. EDT)
The countdown has been proceeding on schedule today. And Sea Launch says weather conditions at the equatorial site are favorable for liftoff.
1918 GMT (3:18 p.m. EDT)
T-minus 60 minutes. The automated launch sequence was initiated at 1458 GMT (10:58 a.m. EDT) today. Currently, the fueling operations are underway. The countdown continues to tick for today's flight of the Sea Launch rocket an hour from now.
Having emerged from bankruptcy and corporate restructuring, Sea Launch looks to get back into the business of hauling commercial satellites to space with a blastoff Saturday.

The Zenit 3SL rocket is targeting a 2018 GMT (4:18 p.m. EDT) launch from its floating platform stationed in the equatorial waters of the Pacific Ocean. The day's available launch window extends 74 minutes to 2132 GMT (5:32 p.m. EDT).

It will be Sea Launch's first mission in two-and-a-half years.

The payload going up this time is Atlantic Bird 7, a powerful communications spacecraft for digital broadcasting and Internet services. The satellite belongs to Paris-based operator Eutelsat.

The Sea Launch fleet reached the launch site a few days ago after steaming for more than a week from the company's home port in Long Beach, California. The ocean-going launch pad known as Odyssey set sail first, followed later by the departure of the Sea Launch Commander vessel, which houses the launch control center, management team and official guests.

Odyssey's ballast tanks were filled with seawater upon arrival at the launch site Tuesday, dropping the converted Norwegian oil-drilling platform to the launch depth of 65 feet. The Sea Launch Commander then pulled alongside Odyssey to allow workers to easily transfer between the two ships.

The rocket was rolled out from its protective hangar aboard Odyssey and erected vertically on the launch pedestal Friday morning.

Odyssey is positioned along the equator at 154 degrees West longitude. The rocket will fly eastward, ultimately releasing its payload high above the Indian Ocean.

The three-stage Zenit booster - making its 31st flight in this configuration - will take just over an hour to complete its role in delivering the Atlantic Bird 7 payload into a planned orbit with a low point of 992 miles and a high point of about 22,208 miles. The injection orbit's inclination will be zero degrees relative to the equator.

Atlantic Bird 7 will use its propulsion system to circularize its orbit to geostationary altitude, where its velocity will match that of Earth's rotation and appear parked at 7 degrees West longitude to provide communications services across the Middle East and Africa.

Launch controllers will spend the last hours of Saturday's countdown making final preparations to the rocket, payload and ground infrastructure. The Sea Launch Commander moves from the Odyssey platform to a safe viewing distance about three miles away.

Fueling operations will get underway about two-and-a-half hours prior to the scheduled liftoff time. A mix of refined kerosene and liquid oxygen comprise the propellant used by all three stages of the launch vehicle.

After igniting its main engine and ascending from the platform, the Zenit 3SL will fly downrange on a due east trajectory hugging the equator. The four-chamber RD-171 engine on the Ukrainian-made first stage ramps up to a maximum of 1.6 million pounds of thrust during its burn lasting two-and-a-half minutes.

Once the first stage separates, the RD-120 powerplant on Ukrainian-made second stage will come to life. During that firing, the payload fairing that shielded the Atlantic Bird 7 satellite during the climb through the denser lower atmosphere will be jettisoned at T+plus 3 minutes, 12 seconds.

Some eight minutes, 29 seconds after blastoff is the point when the second stage will separate from the Russian Block-DM upper stage and payload. Nine seconds later, the motor will ignite for an five-and-a-half minute burn to place itself in a temporary parking orbit with a low point of 112 miles and a high point of 1,153 miles.

Following a lengthy coast phase, the Block-DM will ignite again at T+plus 51 minutes, 31 seconds for a six-minute-long boost to inject Atlantic Bird 7 into its targeted geosynchronous transfer orbit.

Spacecraft separation from the rocket to complete the launch is expected 67 minutes into flight, or 2125 GMT (5:25 p.m. EDT) based on an on-time liftoff.

Check this page during the launch for live updates on the mission's progress.

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