Plasma cathodes for Hall and ion thrusters of high power efficiency, high current, low cost, compactness, are provided. The cathodes employ an orifice cup for containing plasma or discharge outside of the cathode insert.

A mass propelled device includes an evaporation chamber and at least one nozzle. The evaporation chamber includes (i) at least one transparent substrate and (ii) a plurality of nanostructures disposed on a second surface opposite a first surface. The evaporation chamber receives light on the first surface and the plurality of nanostructures excites conduction electrons in response to the received light. The evaporation chamber heats propellent therein using the conduction electrons thereby generating heated propellant. The at least one nozzle produces thrust by exhausting the heated propellent from the evaporation chamber.

A plasma reactor is provided together with a method for generating kinetic energy to propel a craft. The reactor includes an inlet for plasma; a reactor core having an interior chamber and an exterior chamber, the interior chamber being configured to rotate within the exterior chamber; a pair of opposing polar field generators, a first polar field generator connected proximal to an inlet of the interior chamber, and a second polar field generator connected proximal to an outlet of the interior chamber, the pair of polar field generators configured to induce a current in the plasma to generate a toroidal flow therein, wherein the toroidal flow compresses the plasma into a z-pinch flow in a central column between the first polar field generator and the second polar field generator; turbine blades located between the interior chamber and the exterior chamber for generating thrust to convert the z-pinch flow to kinetic energy; and an outlet.

The MPD thruster improvements described here apply to coaxial gas-fed quasisteady self-field devices without auxiliary magnetic fields.

A voltage measurement apparatus for a spacecraft thruster includes a thruster interface having a platform and at least one spacer element configured to attach the platform to the thruster. At least one probe is mounted to the thruster interface with the probe configured to engage an anode assembly of the thruster when the thruster interface is attached to the thruster. The apparatus also includes voltage metering circuitry coupled to the at least one probe, the voltage metering circuitry configured to be powered by the spacecraft thruster when the spacecraft thruster is powered on.

A liquid metal ion source, in particular an ion thruster for propulsion of a spacecraft, comprises a reservoir for the liquid metal, an emitter penetrating a front wall of the reservoir for drawing liquid metal from the reservoir and emitting ions of the liquid metal, and an extractor supported with respect to the reservoir and facing the emitter for extracting and accelerating the ions from the emitter, wherein the reservoir is provided with advancing means for creating an electromagnetic field within the liquid metal in the reservoir to exert a force on the liquid metal in a direction towards the emitter.

A system is described comprising a first controller configured to control a radial arm. The system further comprises a second controller configured to control a probe apparatus motor. The radial arm is configured to move a probe apparatus in a horizontal direction across a horizontal cross-section of a plasma plume generated by a thruster, in response to receiving a first control signal from the first controller. The probe apparatus motor is configured to move a probe, coupled to the probe apparatus, in a vertical direction across a vertical cross-section of the plasm plume, in response to receiving a second control signal from the second controller. And the probe is configured to detect an ion beam current density corresponding to the thruster, based at least in part on a movement of the probe apparatus in the horizontal direction and a movement of the probe in the vertical direction.

One or more embodiments relates to an air-breathing plasma thruster including a thruster wall, an anode, a cathode, and at least one ring electrode. The thruster wall defines a cylindrical channel, the cylindrical channel having a first end and an opposing second end in fluid communication with the first end, where the cylindrical channel is adapted to receive incoming airflow. The anode is at the first end of the channel and the cathode is at the second end of the channel opposite the first end. The at least one ring electrode is positioned on the thruster wall.

A high-power density electric propulsion (EP) system is presented. High-power density functionality of the EP system is provided via thermal management structures that separately manage heat from a discharge chamber with electrically conductive inner/outer walls and an electromagnetic circuit of the EP system. The thermal management structures include separate radiators for rejection of heat from the discharge chamber and the electromagnetic circuit, the heat coupled to the radiators via respective thermal shunts. The thermal shunts include radially inwardly and/or outwardly projecting heat conducting structures that are thermally coupled to the discharge chamber and the electromagnetic circuit. Openings formed in annular structures of the electromagnetic circuit allow radial projection of the thermal shunts.

A spacecraft is disclosed including a frame, an electrical device powered and/or controlled by electrical cables, and a system for orienting the electrical device, which orientation system includes at least two rotary actuators with non-parallel axes (a, b), a junction part between the two rotary actuators, one or more guide forks, arranged outside the junction part and fastened to the latter, each guide fork including fingers configured to support the electrical cables and to form a guide path for said cables so that the electrical cables never exert, on the rotary actuators, a torque higher than the torque capacity of the actuators, at least one of the forks having a main axis which passes through the center of intersection of the axes of rotation of the actuators.