SpaceX Iridium-5 launch
A SpaceX Falcon 9 lifts off March 30 carrying 10 Iridium Next satellites. A new report, and other data, states that SpaceX has recently raised $500 million, a round the company has yet to publicly confirm. Credit: SpaceX

WASHINGTON — Iridium will launch five of its remaining six ground spare satellites on a Falcon 9 rideshare mission in 2023, the company announced Sept. 8.

Iridium said it selected SpaceX for the launch of the five satellites, sharing a launch with other, unnamed payloads. The launch is scheduled for the middle of 2023 from Vandenberg Space Force Base in California.

“We have always said that when the right opportunity presented itself, we would launch many, if not all, of our remaining ground spares, and just such an opportunity came about,” Matt Desch, chief executive of Iridium, said in a statement announcing the launch. “Our constellation is incredibly healthy; however, the spare satellites have no utility to us on the ground.”

Iridium launched its second generation of 75 satellites on eight Falcon 9 missions from January 2017 to January 2019. Seven of the launches were dedicated to Iridium and carried 10 satellites each, while the eighth was a rideshare mission with five Iridium satellites and two NASA-German GRACE-FO Earth science spacecraft.

Iridium indicated earlier this year it was seeking to launch up to five of the remaining six spare satellites, currently in storage in Arizona. Desch said in April that the company was looking for a cost-effective opportunity to launch the satellites rather than continue to pay to keep them in storage. In its second quarter earnings release July 26, Iridium announced it signed a contract for the launch of five satellites for $35 million but did not disclose the launch provider

Iridium signed a contract with small launch vehicle startup Relativity Space in 2020 to launch up to six of the ground spares on Relativity’s Terran 1 rocket. The companies said at the time the spares would be launched individually on an on-demand basis to fill gaps in Iridium’s constellation.

Desch said in the July 26 earnings call that the five satellites covered by the new contract would not be launched by Relativity. “We do have an arrangement still” with Relativity, he said. “It offered the opportunity to launch, but didn’t require a specific number of satellites to launch.”

He hinted in the call that the contract could still be exercised for the final spare satellite, and reiterated that in a tweet after announcing the SpaceX launch contract. “It’s an option for us. We still support Relativity’s development (and the rest of the launch industry),” he wrote. “Focused on this one now though.”

Jeff Foust writes about space policy, commercial space, and related topics for SpaceNews. He earned a Ph.D. in planetary sciences from the Massachusetts Institute of Technology and a bachelor’s degree with honors in geophysics and planetary science...