Will Self-Replication Technology Precede Interstellar Propulsion Technology? The Prospects for Interstellar Self-Replicating Probe & a Human Type III Civilisation Author: Alex Ellery, BSc (Hons), MSc, PhD, P.Eng, C.Eng, C.Phys, C.Math, Professor, Carleton University Abstract Background: Most effort in researching interstellar flight has, not unnaturally, focussed on propulsion technology. There are other salient technologies in particular, self-replication technology acts as an exponential amplifier of both productive value and cost amortisation. A single (or small number of) interstellar spacecraft equipped with an appropriate payload could colonise the entire Galaxy within only 23 generations. Abstract Objectives: We have been developing fundamental capabilities in self-replication technology by exploiting advances in extraterrestrial in-situ resource utilisation and 3D printing. Abstract Methods: Specifically, we shall be describing our experiments in: (i) closed loop extraterrestrial (lunar and asteroidal) resource-based industrial ecosystems from which to construct any kinematic machine; (ii) 3D printing as a universal construction mechanism including 3D printing electric motors; (iii) 3D printing analogue neural network computers as a direct instantiation of the universal Turing machine. We contend that this work tackles the key critical capabilities necessary to realise self-replicating machines. Their sheer utility renders them inevitable – a single self-replicating facility as a payload to a starship opens the prospects for a fully self-replicating probe. Abstract Results: One application of our technology that we are exploring as a transitory concept to our self-replicating spacecraft is a fully 3D printed cubesat including not just structure but also 3D printed motorised reaction wheels and multifunctional structure-embedded 3D neural network circuitry. A miniaturised 2D flat-pack version may be embedded onto a solar sail that might be suitable for a StarChip concept of the Breakthrough Starshot project. Abstract Conclusions: Our embryonic self-replicating probe may offer strategies on searching for physical evidence of prior visitation by postulated extraterrestrial intelligence in our own asteroid belt. Given that self-replication technology is under development with prospects for near-term demonstration, I submit that the first starships that we send will be self-replicating probes. If so, it may be that the transition from an emerging Kardashev Type I civilisation through Type II to Type III civilisation is rapid and transitional. An intriguing corollary is that, given advances in 3D printing biological organs, the self-replicating probes could 3D print entire humans at destination without the necessity for physical transport â€“ the worldship concept may be rendered obsolete.