PARIS — Mobile satellite services operator Iridium Communications is offering a service that provides the satellite platform developed for its Iridium Next constellation, plus on-orbit operations, to customers looking for an inexpensive way to fly their own missions.

McLean, Va.-based Iridium said its Iridium Prime offering uses the same skeletal structure built by Thales Alenia Space of France and Italy for Iridium Next but without the L-band communications payload needed for Iridium’s own mobile communications mission. The platform could host payloads for Earth observation, science, space surveillance, telecommunications or other missions.

Owners of such payloads would benefit from a platform whose nonrecurring engineering costs have been amortized by Thales Alenia Space’s Iridium Next work, making future versions much less expensive compared with purpose-built satellite buses. Satellites purchased under the Iridium Prime program would fly in the same 700-kilometer orbit as the Iridium Next constellation, thereby profiting from Iridium’s intersatellite links and ground infrastructure.

Iridium would operate these satellites as part of an integrated constellation that, in addition to Iridium’s 66 operational satellites, could accommodate up to 66 additional satellites without new spending on its ground network, Iridium Chief Executive Matt Desch said in a Sept. 6 interview. The Iridium ground network is able to handle 140 satellites as it is now, he said.

The Iridium Next satellites are under construction and scheduled for launch by 2017. 

If Iridium Prime collects sufficient customers — enough for as few as one or two additional satellites per year — it will be able to keep open the Thales Alenia Space production line and therefore benefit from the scale economies following the Iridium Next production run. A first Iridium Prime mission could occur by late 2017 or early 2018, Desch said.

Multiple single-satellite and multisatellite systems for Earth observation and communications are in the planning stages or already in development. The owners of these systems generally build their own satellite structures, add their own payloads and negotiate their own terms with launch service providers. Desch said Iridium Prime, by collating demand for low-cost satellite space, will be able to negotiate better prices with launch service providers.

Iridium is investing $3 billion in Iridium Next, with most of the satellites scheduled for launch aboard Space Exploration Technologies Falcon 9 v1.1 rockets.

Iridium is calling Iridium Prime a hosted payload opportunity, but in fact Iridium Prime customers would have as much as 100 percent of the payload capacity of the Iridium Prime satellites they purchase.

To keep costs down, prospective customers will be encouraged to purchase a portion of the Iridium Prime satellite’s payload space, with Iridium rounding up customers with compatible missions to use the same satellite.

For missions that are not overly penalized by Iridium’s orbit, having access to a global network by virtue of Iridium’s intersatellite links relieves them of the obligation to place Earth stations around the world and field their own data relay networks.

Desch said that for Iridium Next and its L-band payload, communications between satellites occur at speeds of between 100 kilobits per second and 1 megabit per second. An Iridium Prime customer using a satellite without the need to share capacity with an L-band communications payload would have intersatellite communications speeds of between 1 and 17 megabits per second and likely more, Desch said.

While video streaming may be more than Iridium Prime could handle, Desch said many Earth observation missions could be accommodated.

The European Space Agency is developing its own data-relay network of two or three satellite payloads in geostationary orbit designed to receive, via laser optical links, imagery from low-orbiting Earth observation satellites to speed image delivery to users. 

Desch said he has not yet completed negotiations with Thales Alenia Space on the price of an Iridium Prime platform, but that he has enough of an idea to say that most owners of payloads adaptable to a low Earth orbit would save 50 percent or more on satellite and launch costs by using Iridium Prime.

The Iridium Prime initiative is not based on any anticipated order from the U.S. Air Force’s Space and Missile Systems Center, which has issued a request for quotations for hosted payload opportunities for Air Force sensors. But he said the Iridium Prime concept “is exactly what they [the U.S. Air Force] are looking for.”

Peter B. de Selding was the Paris Bureau Chief for SpaceNews.