Interstellar probe using a solar sail: Conceptual design and technological challenges

NASA's Interstellar Probe, conceived to travel to 200-400 AU, will be the first spacecraft designed specifically to explore the unknown regions beyond the solar system and directly sample the dust, neutrals and plasma of the surrounding interstellar material. Here we present the mission concept developed by NASA's Interstellar Probe Science and Technology Definition Team in 1999 and discuss the technological challenges it presents. The Team selected a solar sail concept in which the spacecraft reaches 200 AU in 15 years. This rapid passage is made by using a 400-m diameter solar sail and heading first inward to similar to0.25 AU to increase the radiation pressure. The Probe then heads out in the interstellar upwind direction at similar to14/AU year, about 5 times the speed of the Voyager 1 and 2 spacecraft. Advanced lightweight instruments and spacecraft systems, as well as solar sail propulsion, are needed to achieve these high speeds. The spacecraft coasts to 200-400 AU, exploring the Kuiper Belt, the boundaries of the heliosphere, and the nearby interstellar medium.