Mobile Communications Satellite Launches Into Orbit

Thesecond step in a $1.5 billion program to create a mobile broadbandcommunications network spanning the globe for users at sea, in the air and onland roared into space today.

The Inmarsat 4-F2 satellitelifted off from a floating platform in the equatorial Pacific Ocean at 1407 GMT(9:07 a.m. EST) atop a commercial Sea Launch Zenit 3SL rocket.

The three-stage boostertook about 85 minutes to haul the 13,108-pound (5,945-kilogram) spacecraft to the desiredaltitude.

When it enters service fromgeostationary orbit 22,300 miles (35,888 kilometers) above Earth next year, the craft will join theInmarsat 4-F1 satellite that was successfully launchedon Lockheed Martin's Atlas 5 rocket in March from Cape Canaveral, Florida.Together, the two craft will deliver broadband communications to 85 percent ofthe world.

"Putting almosthalf-megabit data speeds for people to access globally where terrestrialnetworks don't go we see as a fundamental service," said Inmarsat CEOAndrew Sukawaty. "It's really about taking the office with you whereterrestrial networks don't go economically."

Inmarsat's newestgeneration of satellites come with the tag line "broadband for a mobileplanet." Built in Europe by EADS Astrium, the Inmarsat 4-series spacecraftwill provide office-like broadband services such as Internet, email, voice anddata-relay using laptop and palm-sized terminals.

"It will transform theway people who are out of reach of other communications access broadbandservices," said Frank August, Inmarsat's regional director for NorthAmerica.

The Inmarsat 4-series ofsatellite also continue the existing lower-data-rate capacity currently offeredby the London-headquartered company for maritime, air and emergency services,and enhanced navigation signals for air traffic uses.

"Basically, it isgoing to expand our services and extend the life of our service to the end ofthe next decade," Sukawaty said.

The sophisticatedsatellites transmit over 200 spot beams to deliver strong signals to the smallreceivers. Each craft has a giant unfurlable antenna reflector stretching 30 by39 feet.

The new craft are 60 timesmore powerful and have 20 times more capacity than their predecessors, theInmarsat 3-series of satellites.

Inmarsat 4-F1 is operatedover the equator at 64 degrees East over the Indian Ocean to cover Europe,Africa, the Middle East and Asia. The sister satellite launched today --Inmarsat 4-F2 -- is scheduled to be placed at 53 degrees West to serve SouthAmerica, most of North America, the Atlantic Ocean and part of the PacificOcean.

Inmarsat has built the F3spacecraft as a backup for the first two satellites. If not needed as areplacement, the craft could be deployed over the Pacific as the third memberof this broadband satellite constellation. Inmarsat has contracted with Atlas 5for another launch.

Today's liftoff was SeaLaunch's fourth flight of 2005 and 18th overall since debuting in 1999.

"All indications arethat this was an absolutely outstanding launch. It launched right at thebeginning of the launch window, went right down the center of the line, andeverything was right on the mark," said Sea Launch president Jim Maser.

The Zenit 3SL rocket usesUkrainian-made Zenit first and second stages to power the first eight minutesof flight and a Russian-manufactured Block DM-SL upper stage to accelerate thepayload to the target altitude for deployment.

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Spaceflight Now Editor

Justin Ray is the former editor of the space launch and news site Spaceflight Now, where he covered a wide range of missions by NASA, the U.S. military and space agencies around the world. Justin was space reporter for Florida Today and served as a public affairs intern with Space Launch Delta 45 at what is now the Cape Canaveral Space Force Station before joining the Spaceflight Now team. In 2017, Justin joined the United Launch Alliance team, a commercial launch service provider.