Abstract: A thruster system for use in a spacecraft combines chemical and electric or electrothermal propulsion. To that end a thruster may comprise a cavity including at least one inlet to receive a first fluid and a second fluid configured to chemically react with the first fluid within the cavity to generate a reaction product. Alternatively, the cavity may be configured to receive a monopropellant configured to chemically decompose within the cavity. The thruster system further comprises an energy source coupled to the cavity and configured to heat or ionize material within the cavity by emitting electromagnetic radiation. Still further, the thruster system comprises a nozzle provided at one end of the cavity and configured to direct heated material out of the cavity to generate thrust.