We propose a roadmap to a program that will lead to sending relativistic probes to the nearest stars. To do so requires a fundamental change in our thinking of both propulsion and our definition of what a spacecraft is. In addition to larger spacecrafts capable of human transportation, we consider “wafer sats”, wafer-scale systems weighing no more than a gram. The wafer sats would include integrated optical communications, optical systems, and sensors. These crafts, combined with directed energy propulsion, could be capable of speeds greater than 0.25 c.

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