Iridium operates the only satellite constellation that provides truly global coverage — every square metre of the Earth's surface, including the poles, oceans, and airways. The Iridium NEXT constellation, completed in 2019, comprises 66 operational satellites in 6 orbital planes at approximately 780 km altitude, plus 9 in-orbit spares.
History
The original Iridium constellation was conceived at Motorola in the late 1980s and launched between 1997 and 1998. The company famously filed for bankruptcy in 1999 after failing to attract enough subscribers to justify the $5 billion deployment cost. A group of investors acquired the constellation for $25 million and relaunched the service, finding profitable niches in maritime, aviation, military, and emergency communications where terrestrial and GEO coverage does not reach.
Between 2017 and 2019, SpaceX launched all 75 Iridium NEXT satellites across 8 Falcon 9 missions — one of the earliest large-scale Falcon 9 constellation deployment campaigns. The new satellites feature cross-linked L-band and Ka-band payloads, enabling Iridium Certus broadband services alongside legacy voice and data.
Services
Iridium Certus is the broadband service, offering speeds up to 704 kbps (midband) and 352 kbps over L-band terminals. While far slower than Starlink, Certus provides coverage everywhere, including polar regions where LEO broadband constellations in inclined orbits cannot reach. Iridium Push-to-Talk provides satellite-based group communications for field operations. Iridium Short Burst Data (SBD) powers IoT/M2M applications, with over 1.5 million active IoT devices on the network. Iridium GO! provides smartphone connectivity via a portable hotspot device.
Key Markets
Maritime is Iridium's largest market, with satellite communications mandatory under the Global Maritime Distress and Safety System (GMDSS) — Iridium was approved as a GMDSS provider in 2020. Aviation is the fastest-growing segment, with Iridium providing cockpit safety communications and, through partners like Gogo, inflight broadband. Military users (primarily the US Department of Defense under the EMSS contract) represent a stable, high-margin segment.
Apple's Emergency SOS via Satellite feature, launched on iPhone 14 in 2022, uses the Globalstar network rather than Iridium — but Iridium has since partnered with Qualcomm to enable direct-to-device satellite messaging on Android devices, expanding the potential consumer market significantly.