Starlink

Current obstacles

Physics limits

• Radio spectrum caps capacity per areaEach beam covers a cell tens of km wide, and all users in it share a fixed slice of spectrum. Shannon's law caps the bits per hertz, so dense towns hit a ceiling that more satellites overhead only partly lift.
• Low orbits decay, so satellites are short-livedAt about 550 km the thin air still drags on satellites. They need thrusters to stay up and fall back within about five years once dead, so the fleet must be replaced continuously.
• Crowded orbits raise the collision riskThousands of satellites at similar heights must dodge each other and debris. A single collision at 10 km/s makes thousands of fragments, and the risk grows faster than the number of objects.