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Inmarsat launches third satellite in broadband constellation

Inmarsat has successfully launched and acquired the third Inmarsat-4 satellite, the company said Aug. 19.

Launched on a Proton Breeze M rocket from the Baikonur Cosmodrome in Kazakhstan Aug. 18 (Aug. 19 local time), the satellite was detected by Inmarsat’s tracking station in Fucino, Italy, which confirmed the presence of the satellite high above Earth while it was still coupled to the Breeze M launch vehicle. Launch provider ILS later confirmed successful spacecraft separation.

The satellite is the third in the I-4 constellation, concluding a decade of development and a $1.5 billion investment. The current constellation of two Inmarsat-4 satellites delivers mobile broadband services to 85 percent of the world’s landmass, covering 98 percent of the world’s population. The third I-4 will complete the global coverage for Inmarsat’s broadband services.

The I-4 F3 satellite will now undergo a period of deployment and several weeks of comprehensive tests and maneuvers before being positioned in geostationary orbit at 98 degrees west.

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