File image of Rockot launch. Photo: Eurockot

A pair of spare satellites for the Iridium mobile communications network were successfully launched into space today by a Rockot vehicle from Plesetsk Cosmodrome in Northern Russia. The spacecraft are part of a plan designed to ensure Iridium's constellation operates through 2010.

Liftoff occurred at 0933 GMT (5:33 a.m. EDT). The mission, carried out by Bremen, Germany-based Eurockot Launch Services, placed the satellites into orbit 650 km above the planet at an inclination of 86.6 degrees.

Today's launch brought to 95 the total of Iridium satellites propelled into space during 22 rocket flights. Beginning in May 1997, 60 spacecraft were launched by the 12 Boeing Delta 2 rockets, 21 satellites were carried aloft by three Russian Proton rockets, 12 flew aboard six Chinese Long March rockets and now Rockot has carried two. Remarkably, Iridium has never suffered a launch failure.

The Iridium constellation relies upon 66 primary satellites working together in six groupings of 11 spacecraft each to cover virtually the entire planet from low-Earth orbit.

The satellites launched today will join a dozen others that serve as orbiting spares, ready to replace any of the primary 66 as the craft age and fail in the future. By having the replacement satellites already in space, the spares are prepared to enter the constellation and fill any holes as they open up, keeping the Iridium system rejuvenated and functioning.

An artist's concept of the Iridium satellite constellation. Credit: Motorola

Engineers believe the large number of replacement satellite will ensure the Iridium system remains healthy through mid-2010, much longer than originally designed.

"The successful launch and deployment of two additional in-orbit spares further demonstrates that Iridium is a viable company with solid fundamentals and tremendous market opportunities," said Gino Picasso, Iridium Satellite CEO. "Combined with our ever-expanding global distribution network, Iridium is meeting and exceeding our business plan objectives."

The original Iridium company rolled out commercial service in November 1998, but failed to attract a sufficient number of subscribers due to the pricey $3,000 phone and $7 per minute airtime fees.

Iridium LLC lapsed into bankruptcy in August 1999 and by spring 2000, without a suitable buyer found, it appeared the satellite fleet would be driven into Earth's atmosphere to burn up.

The $5 billion system was rescued in December 2000 when Dan Colussy, an aviation industry veteran, purchased the assets of Iridium LLC, including the satellite constellation and the terrestrial network for about $25 million.

The miracle rebirth of Iridium was completed in March 2001 when commercial service was relaunched.

The new company -- Iridium Satellite LLC -- debuted with cheaper prices and set out to target specific industries that it believed would subscribe to the system for communications to remote areas of the planet where terrestrial telephone networks do not exist, like construction, emergency services, maritime, mining, forestry, oil and gas and aviation.

The U.S. Department of Defense is an existing Iridium customer under a multi-year contract for unlimited airtime for up to 20,000 government users.