Power Systems for Miniature Interstellar Flyby Probe

In the last few years, the concept that an ultra-lightweight probe could be sent to one of the nearby stars pushed by a laser beam reflecting from a lightweight sail has moved from science fiction into conceptual design. A candidate interstellar sail envisions a two- to three-gram "starchip" micro probe, flying past a planet of Proxima Centauri after a 20 year voyage. With the probe moving at 60,000 km/sec, the flyby encounter at the target planet is within 1 AU of the target planet at most a few hours, and in the case of an encounter with a planet of Proxima Centauri, is close to the star for only a few minutes. With current technology, no power system exists that can produce the required power with a mass of less than one gram.