Global mobile service provider Iridium has announced that its next-generation satellites will be taken into orbit using the Falcon rocket built by SpaceX.
The contract is worth $482m (£327m), making it the largest commercial launch deal ever signed.
The Iridium NEXT satellites will be launched into low-Earth orbit from Vandenberg Air Force Base in California between 2015 and 2017.
"We are proud to partner with SpaceX, and want to congratulate [PayPal co-founder] Elon Musk and the entire SpaceX team on its successful inaugural Falcon 9 launch," said Matt Desch, chairman and chief executive of Iridium.
"SpaceX offered us the best value coupled with an unwavering commitment to flawless performance and reliability. SpaceX has combined the best of aerospace and commercial best practice to design reliable and cost-effective access to space, and Iridium will be the beneficiary of that effort."
The Falcon rocket, after some teething problems, has successfully placed dummy packages in orbit, and the contract will be a major boost to the company set up by Musk using money from the sale of PayPal.
The contract calls for 24 flights to place the satellites in orbit over a two-year period. The satellites will maintain Iridium's global coverage and allow it to upgrade to new voice and data services.
"Iridium NEXT is now our largest commercial satellite launch customer and we are excited to play such an integral part in the most significant commercial space programme underway today," said Musk.
"SpaceX greatly appreciates Iridium's efficient approach to satellite production, an approach we share when it comes to our launch vehicles.
"As the next generation of the world's only global satellite constellation that reliably covers 100 per cent of the Earth's surface, the implementation of the Iridium NEXT satellites will mark a significant achievement in mobile satellite communications, and SpaceX is looking forward to making it happen."
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