🔍 Key Concepts

• Iridium satellite constellation characteristics (orbit type and number of satellites) • Difference between bent‑pipe (store-and-forward) satellites vs. inter‑satellite links • What geostationary means and which systems use it (e.g., Inmarsat vs. Iridium)

💭 Think About

• Think about whether Iridium satellites stay fixed over one point on the equator, or move quickly across the sky in low Earth, near-polar orbits. • Consider whether Iridium is designed to delay calls until a satellite sees a ground station, or to move traffic rapidly across the constellation. • Ask yourself: does Iridium rely on another type of satellite (like geostationary ones) to complete its links, or is it a self-contained network?

✅ Before You Answer

• Verify whether Iridium uses low Earth, near-polar orbits rather than geostationary orbits. • Check if Iridium satellites have inter-satellite links that let them pass traffic among themselves. • Eliminate any option that depends on a store-and-forward delay or on geo-stationary satellites if that does not match Iridium’s known architecture.