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Sunday, June 23, 2019

Ariane 5 lofts satellites for AT&T, Eutelsat

SANTA BARBARA, California — A European Ariane 5 rocket successfully launched two communications satellites June 20.


The heavy lift launcher took off from Europe’s spaceport in Kourou, French Guiana, at 5:43 p.m. Eastern, carrying the T-16 satellite for AT&T’s DirecTV business, and the Eutelsat-7C satellite for French operator Eutelsat Communications.


The 6,330-kilogram T-16 satellite, built by Airbus Defence and Space, separated from the rocket’s upper stage 28 minutes later, followed by the 3,400-kilogram Eutelsat-7C satellite from Maxar Technologies 34 minutes after liftoff.


The launch is the fifth this year for European launch provider Arianespace of Evry, France, and the second in 2019 using an Ariane 5 rocket. Arianespace is roughly a year away from the maiden flight of the next-generation Ariane 6, which is designed to be more cost competitive against vehicles such as SpaceX’s Falcon 9.


AT&T’s T-16 satellite is designed to operate from five different orbital slots, and will cover the United States. The satellite’s launch comes some seven months after AT&T Communications CEO John Donovan said the company had already launched its last satellite.


In a statement to SpaceNews, AT&T said T-16 is the last satellite currently planned.


“This new satellite will replace several satellites that are reaching end of life,” AT&T said. “We currently have no future planned satellite launches.”


AT&T has been increasing its focus on internet streaming services as its satellite television subscriber base wanes. The company reported a loss of 544,000 “premium TV subscribers” from January to March 31, lowering the total count to 22.4 million.


For Eutelsat, today’s launch brings additional capacity to Africa, Europe and the Middle East for a mix of television broadcast and internet connectivity services. Eutelsat, which operates a fleet of roughly 40 satellites, plans to co-locate Eutelsat-7C with the Eutelsat-7B satellite at the 7 degrees east orbital slot. The company will then move Eutelsat-7A to another location as part of its fleet optimization strategy.


Eutelsat-7C carries 44 Ku-band transponders, replacing capacity from Eutelsat-7A and expanding coverage at 7 degrees east by 19 transponders.


Eutelsat-7C is the first all-electric satellite from Maxar Technologies. The spacecraft will take close to four months to climb from a geostationary transfer orbit to the geostationary arc 36,000 kilometers above the Earth.


Maxar said in a statement that more than 30 spacecraft it built have used some form of electric propulsion, collectively topping 100,000 hours of thruster operation.


Electric propulsion requires less mass than chemical propulsion, but is a slower means of propelling a spacecraft. AT&T’s T-16 satellite from Airbus has chemical propulsion for faster orbit raising, coupled with electric propulsion for station keeping.


In a speech following the launch, Paul Estey, Maxar’s chief operations officer, said Eutelsat-7C is the first satellite to carry Maxar’s more powerful second-generation lithium-ion power generation system. The satellite also carries a photonics payload to demonstrate technology for more efficient payloads in the future, he said. Photonics payloads have the potential to reduce spacecraft mass compared to current radio-frequency systems.


Arianespace CEO Stéphane Israël said the launch provider’s next mission is July 5 using a Vega light-lift rocket. That mission will carry the first of two Falcon Eye surveillance satellites for the United Arab Emirates.









#Space | https://sciencespies.com/space/ariane-5-lofts-satellites-for-att-eutelsat/

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