Dan M. Goebel, PhD, is a Fellow and Senior Research Scientist at the Jet Propulsion Laboratory, and Adjunct Professor of Aerospace Engineering and Electrical Engineering at UCLA. He is a Member of the National Academy of Engineering, and also a Fellow of the National Academy of Inventors, the IEEE, the AIAA, and the American Physical Society. He is presently the Chief Engineer of the NASA Psyche Mission. Ira Katz, PhD, is an Aerospace Consultant specializing in electric propulsion and spacecraft charging. He retired from the Jet Propulsion Laboratory after leading the Electric Propulsion group and researching electric propulsion physics. Previously, he worked in industry investigating spacecraft charging and headed the team that developed the NASA Charging Analyzer Program, NASCAP. Ioannis G. Mikellides, PhD, is a Senior Research Scientist at the Jet Propulsion Laboratory and a Fellow of the AIAA. In the last three decades his research on the theory and numerical simulation of plasmas has spanned a wide range of applications, both in and beyond electric propulsion. He is also the main author of the scientific plasma codes OrCa2D and Hall2De, which have been supporting NASA’s space flight qualification of hollow cathodes and Hall thrusters.