Precursor missions to interstellar exploration

This paper summarizes material developed over a three-month period by a JPL team of mission architects/analysts and advanced technology developers for presentation to NASA Headquarters in the summer of 1998. A preliminary mission roadmap is suggested that leads to the exploration of star systems within 40 Light years of our Solar System. The precursor missions include technology demonstrations as well as missions that return significant new knowledge about the space environment reached. Three propulsion technology candidates are selected on the basis of allowing eventual travel to the nearest star taking 10 years. One of the three propulsion technologies has a near term version applicable to early missions (prior to 2010)-the solar sail. Using early sail missions other critical supporting technologies can be developed that will later enable Interstellar travel. Example precursor missions are sail demonstration missions, including a solar storm warning mission demonstrating a simple sail, a solar polar imaging mission using an intermediate sail, and a 200-AU Heliosphere Explorer mission using an advanced solar sail. Missions later than these on the roadmap will require types of fusion propulsion, antimatter-matter annihilation propulsion, or enhancements to the sail technology to propel spacecraft to the stars in the relatively short trip times desired. The sail enhancement envisioned at this time uses an Earth-based laser in what is termed as a beamed-energy approach. Mission and technology strategy, science return, and potential mission spin-offs are described