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Two long-running satellite phone and messaging constellations, both now agreed to be acquired (Iridium by Rocket Lab, Globalstar by Amazon): comparing coverage, network architecture, data speeds, subscribers and Apple Emergency SOS.
| Metric | Iridium | Globalstar |
|---|---|---|
| Headquarters[1,3] | McLean, VA | Covington, LA |
| Publicly Traded[2,3] | Yes (IRDM, Nasdaq) | Yes (GSAT, Nasdaq) |
| Pending Acquisition (Oct 2026)[2,4] | Rocket Lab agreed to acquire Iridium (agreement June 28, 2026; stockholders approved Sep 24, 2026; closing expected mid-2027) | Amazon agreed to acquire Globalstar (agreement Apr 13, 2026; closing expected in 2027) |
| Current Constellation[5,7,8] | Iridium NEXT, launched Jan 2017 to Jan 2019 (five more spares in May 2023) | Second generation, launched 2010 to 2013; 8 replacement satellites launched Aug 15, 2026, 9 more on order |
| Satellites[1,5,6] | 66 operational in six polar planes, plus in-orbit spares | 24 satellites (Apple, 2022), plus the 8 replacements now in commissioning |
| Orbital Altitude[1,8] | About 778 km (483 miles) | About 1,410 km |
| Coverage[1,3] | Global, including the poles | Designed for latitudes between 70 degrees north and 70 degrees south |
| Inter-Satellite Links[1] | Yes: crosslinked mesh, little need for local ground stations | No: "bent pipe", traffic goes straight down to gateways |
| Data Services[1,3] | Legacy 2.4 Kbps narrowband; Iridium Certus up to 704 Kbps (launched Jan 2019) | Duplex voice and data, SPOT messengers, Commercial IoT |
| Consumer Device Partners[1,6] | Partners such as Garmin build devices on Iridium; Iridium NTN Direct (standards-based D2D) expected to launch in 2026 | Apple: Emergency SOS via satellite on iPhone since iPhone 14 (2022) |
| Largest Customer[1,3] | U.S. government: about 29% of 2025 revenue | Apple: 63% of 2025 revenue; Apple owns 20% of the Globalstar SPE that holds the new network |
| IoT / M2M Services[1,3] | Iridium SBD transceivers, Iridium Certus 9770 and 9704 | Commercial IoT devices and SPOT trackers |
| Subscribers (Dec 31, 2025)[1,3] | About 2,537,000 billable subscribers | About 791,000 MSS subscribers |
| Revenue (FY2025)[1,3] | $871.7M | $273.0M |
| Next Satellites[1,3] | No new constellation announced; new services (NTN Direct) run on the existing satellites | Third-generation C-3 System: more than 50 satellites ordered from MDA Space ($775.0M contract), to launch on SpaceX |
Iridium's network has 66 operational satellites in near-polar orbits, linked to each other by radio crosslinks, so traffic can be routed across the constellation in space with little need for local ground stations, and coverage reaches the poles. The U.S. government accounted for about 29% of Iridium's 2025 revenue. The Iridium NEXT satellites, launched between January 2017 and January 2019, enabled Iridium Certus, launched in January 2019 with speeds now up to 704 Kbps, against 2.4 Kbps for the legacy narrowband service.[1,7]
Globalstar carries Apple's Emergency SOS via satellite, introduced with iPhone 14 in 2022, and Apple accounted for 63% of Globalstar's 2025 revenue. Globalstar's satellites use a "bent pipe" design without crosslinks, sending traffic straight down to gateways, and its constellation is designed for latitudes between 70 degrees north and south. Eight replacement satellites built by MDA Space launched on August 15, 2026, and a third-generation system of more than 50 satellites is on order. Both companies also sell IoT services: Iridium through its SBD and Certus transceivers, Globalstar through its Commercial IoT and SPOT products.[3,5,6]
Track both companies on SpaceNexus