Science Objectives of an Interstellar Probe Mission to 200-400 AU
Paulett Liewer
Jet Propulsion Laboratory, Pasadena, CA
Sending a spacecraft beyond the heliopause to begin the exploration of our local galactic neighborhood will be one of the grand scientific enterprises of the next century. Interstellar space is a largely unknown frontier that holds many of the keys to understanding our place in the galaxy. NASA's Interstellar Probe will be the first spacecraft designed to explore the nearby interstellar medium and its interaction with our solar system. As envisioned by NASA's Interstellar Probe Science and Technology Definition Team, the spacecraft will be propelled by a solar sail to reach >200 AU in 15 years. This talk summarizes the science goals of the Interstellar Probe mission developed by the team.
The rapidly expanding solar atmosphere - the solar wind - creates a bubble called the heliosphere that shields our solar system from the interstellar plasma and magnetic fields, and most of the cosmic rays and dust that comprise the local galactic neighborhood. The Interstellar Probe mission is designed to exit this bubble and begin exploring the space between the stars. In the course of this journey, Interstellar Probe will investigate unknown aspects of the outer solar system, explore the boundaries of the heliosphere to reveal how a star interacts with its environment, and directly sample the properties of the nearby interstellar medium. These studies will address key questions about the nature of the primordial solar nebula, the structure and dynamics of our heliosphere, the properties of organic material in the outer solar system, the nature of other stellar systems that may also harbor planets, the chemical evolution of our galaxy, and the origins of matter in the earliest days of the universe. To carry out these exploratory studies, Interstellar Probe will include a comprehensive suite of sensors designed to measure the detailed properties of the plasma, neutral atoms, energetic particles, magnetic fields, cosmic rays and dust at the heliospheric boundaries and in the nearby interstellar medium.