Iridium Communications Inc. (NASDAQ:IRDM) has announced that the fifth Iridium NEXT launch has been targeted by SpaceX for March 18, 2018 at 8:19 am PDT (15:19 UTC) from Vandenberg Air Force Base in California.

Artistic rendition of an Iridium NEXT satellite.

The first of four launches planned for 2018, Iridium-5 will deliver 10 more Iridium NEXT satellites to orbit, bringing the total number of new satellites deployed to 50. This launch will use the same Falcon 9 first stage as the Iridium-3 launch that took place in October 2017 and begin a rapid-cadence launch schedule targeting completion of the Iridium manifest by mid-2018.

The Iridium network is comprised of six polar orbiting planes, each containing 11 operational cross-linked satellites, for a total of 66 satellites in the active constellation. The Iridium-5 launch will deliver the new satellites to orbital plane 1, where all 10 will go directly into service after testing and validation.

Following Iridium-5, the Iridium-6 Rideshare mission is targeted for mid-to-late April.  The Rideshare will carry five Iridium NEXT satellites and the twin satellites for the NASA/German Research Center for Geosciences (GFZ) Gravity Recovery and Climate Experiment Follow-On mission. The final four launches will bring a total of 35 new satellites to space, completing the constellation of 66 operational satellites and 9 in-orbit spares.

Iridium NEXT is the company's $3 billion, next-generation, mobile, global satellite network scheduled for completion in 2018. The constellation features 66 active satellites, plus nine on-orbit spares. In total, 81 new satellites are being built, with the six remaining satellites serving as ground spares. Iridium NEXT will replace the company's existing global constellation in one of the largest technology upgrades ever completed in space.  It represents the evolution of critical communications infrastructure that governments and organizations worldwide rely on to drive business, enable connectivity, empower disaster relief efforts and more.

Matt Desch, Iridium's CEO, stated that the home stretch is now being entered by the company. This is going to be a monumental year for Iridium as the constellation refresh is completed by the company. In addition to four launches, the testing and validation processes will be continued for the firm's new specialty broadband service, Iridium CertusSM, with commercial launch scheduled for later this year.