Physicists from the U.S. Department of Energy’s (DOE) Princeton Plasma Physics Laboratory (PPPL) are providing critical expertise for the first full campaign of the world’s largest and most powerful stellarator, a magnetic confinement fusion experiment, the Wendelstein 7-X (W7-X) in Germany. The fusion facility resumes operating on August 28, 2017, and will investigate the suitability of its optimized magnetic fields to create steady state plasmas and to serve as a model for a future power plant for the production of a “star in a jar,” a virtually limitless source of safe and clean energy for generating electricity.