The H9 is a single channel magnetically shielded Hall thruster jointly developed by NASA’s Jet Propulsion Laboratory, the University of Michigan and the Air Force Research Laboratory. The thruster has a nominal power level of 9 kW and a similar design to other state-of-the art Hall thrusters. The thruster is designed to operate between 300 and 800 V with a center mounted lanthanum hexaboride (LaB6) hollow cathode. It is notable for its high efficiency (63% at 800 V) and specific impulse (up to 2900 seconds).

This thruster takes heavy design heritage from the H6, a 6-kW laboratory thruster. Additionally, the thruster incorporates magnetic shielding technology which is a magnetic field design that shields the thruster walls from the plasma to increase the lifetime up to three orders of magnitude. This technology has enabled the application of Hall thruster on deep space missions. However, it is a relatively nascent technology, meaning that continued studies are needed to fully understand the implications of the technology on thruster operation (such as increased pole erosion). In addition to providing a platform to study magnetic shielding, the H9 Hall thruster provides a platform to continue research on the open questions around Hall thrusters on state of the art technology. Namely, these include electron transport and facility effects.

Work by Cusson has throttled the thruster through its full operating table and established baseline performance measurements, including thrust, oscillation characteristics, and plume symmetry.

Since its first firing in 2016, the H9 has been used in various experimental campaigns, including those by Brown and Durot, to better understand electron transport in the channel of a Hall thruster. On-going work with the thruster include experimental campaigns to characterize the acceleration region (using laser induced fluorescence) and facility effects as well as two-dimensional modeling of the plasma properties.