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One step closer to Reagan's Strategic Defense Initiative.

MichaelCollins 4y ago
It's now the Space Development Agency's (SDA) National Defense Space Architecture (NDSA). But yes, Starlink looks a hell of a lot like the Transport Layer of the NDSA, which is meant to be a mesh network comprising of thousands of satellites in LEO. Either Starlink is the Transport Layer of NDSA, or it proves that SpaceX has the technical ability to create the Transport Layer (no other company does.)
- Dylan16807 4y ago
  I really wouldn't put it that way, though. The core part of SDI, the missile defense, isn't part of NDSA. And the "transport layer" is something new to NDSA as far as I can tell.
  - MichaelCollins 4y ago
    It depends on which version of SDI you're talking about, there were numerous proposed architectures using different technologies, updated through the years as technology changed. In several of the proposals, orbital Boost Surveillance and Tracking Systems (BSTS) would communicate with orbital interceptors using inter-satellite laser links. Brilliant Pebbles particularly called for thousands of orbital interceptors with IR sensors to track missiles, but to arrange an intercept in time a Pebble would need to receive track information from the BSTS, or other pebbles. The challenge of doing that with thousands of pebbles was one of the factors that sank the proposal (the other big problem being the difficulty of actually launching thousands of interceptors into LEO.) The mesh network aspect of NDSA / Starlink is new insofar as they've now figured out how to do what they wanted to do back then. Space-based interceptors are missing from NDSA as it's described in public. But all the technical challenges have been resolved, what remains is the political challenge. Since the space-based interceptors are the politically contentious part, if they were going to do this it would make sense for them to build the 'benign' parts first while not talking about the rest.

It's now the Space Development Agency's (SDA) National Defense Space Architecture (NDSA). But yes, Starlink looks a hell of a lot like the Transport Layer of the NDSA, which is meant to be a mesh network comprising of thousands of satellites in LEO. Either Starlink is the Transport Layer of NDSA, or it proves that SpaceX has the technical ability to create the Transport Layer (no other company does.)

Dylan16807 4y ago
I really wouldn't put it that way, though. The core part of SDI, the missile defense, isn't part of NDSA. And the "transport layer" is something new to NDSA as far as I can tell.
- MichaelCollins 4y ago
  It depends on which version of SDI you're talking about, there were numerous proposed architectures using different technologies, updated through the years as technology changed. In several of the proposals, orbital Boost Surveillance and Tracking Systems (BSTS) would communicate with orbital interceptors using inter-satellite laser links. Brilliant Pebbles particularly called for thousands of orbital interceptors with IR sensors to track missiles, but to arrange an intercept in time a Pebble would need to receive track information from the BSTS, or other pebbles. The challenge of doing that with thousands of pebbles was one of the factors that sank the proposal (the other big problem being the difficulty of actually launching thousands of interceptors into LEO.) The mesh network aspect of NDSA / Starlink is new insofar as they've now figured out how to do what they wanted to do back then. Space-based interceptors are missing from NDSA as it's described in public. But all the technical challenges have been resolved, what remains is the political challenge. Since the space-based interceptors are the politically contentious part, if they were going to do this it would make sense for them to build the 'benign' parts first while not talking about the rest.