The LEO satellite proliferation is driving R&D in and deployment of Free Space Optical (FSO) connectivity, both within the networks and for extended hybrid networks combining terrestrial and non-terrestrial elements. This is part of a wider effort to develop architectures for global hybrid networks embracing and extending 5G. There is also growing interest in FSO at the surface, as an alternative to fiber optic, because it can be easier and faster to deploy with no need to lay cable either under or above ground. The strongest current momentum comes from the big LEO satellite constellations, especially Starlink, Amazon’s Project Kuiper, and the US Pentagon’s Space Development Agency (SDA). The initial FSO focus here was on inter-satellite links for greater resiliency…