A neutralizer suitable for use in an ion engine comprises a halogen gas source and an electrode tube comprising an inlet opening connected to the halogen gas source for supplying a halogen gas provided by the halogen gas source into the electrode tube, a discharge space for generating a plasma from the halogen gas supplied into the electrode tube, and an outlet opening for discharging the plasma generated in the discharge space and free electrons from the electrode tube. An electron emitter is arranged in the discharge space of the electrode tube, which is at least partially made of tungsten, a tungsten alloy or a tungsten composite material containing at least one of iridium, rhenium, ruthenium, rhodium and osmium.

An intake system for an atmosphere-breathing electric thruster is disclosed, comprising an inlet for inflow of atmosphere particles, an outlet for coupling to the thruster for fueling collected atmosphere particles to the thruster, a collector arranged between the inlet and the outlet comprising multiple channels for allowing inflowing atmosphere particles to pass through the channels towards the outlet, the channels defining an inlet area and a length, wherein a position of at least part of the channels is adjustable to alter at least one of the inlet area and the length.

Methods and apparatuses for emitting electrons from a hollow cathode are provided. The cathode includes a plasma holding region configured to hold a plasma, a gas supply source configured to supply gas to the plasma holding region, and an orifice plate disposed on a periphery of the plasma holding region. The orifice plate comprises a plurality of openings constructed to receive electrons from the plasma. The plurality of openings decouple gas conductance and electrical conductance across the orifice plate. The diameters of the plurality of openings are within a range of 20%-60%, inclusive, of a diameter of a circular opening with an area equal to a sum of the areas of the plurality of openings.

A plasma engine includes a plasma source that generates ions from molecular gas species received at a gas input where at least some of the ions generated are atomic species ions. An ion extractor is configured to extract ions from the plasma source with an electric field. A housing comprising a recombination region receives ions extracted from the ion extractor. At least some of the atomic species ions recombine into molecular species in the housing, thereby releasing energy for thrust.

A method and apparatus for forming torsional magnetic reconnection, and converting stored magnetic energy into charged particle kinetic energy and particle acceleration, is claimed. A torsional magnetic reconnection apparatus generally comprises (1) a vacuum environment housing (2) a plurality of conducting coils to form a magnetic field fan-spine topology and (3) a plasma generation device providing an azimuthal magnetic field perturbation such that current sheets are formed and magnetic reconnection processes can occur. Electric current energization of the plurality of conducting coils generates a potential magnetic fan-spine topology. A simultaneous capacitor bank discharge forms and axially drives a plasma sheath, featuring an azimuthal magnetic field, toward the fan-spine magnetic null that forces the diffusion of magnetic flux through the plasma. This magnetic to plasma kinetic energy conversion process accelerates charged particles far away from the reconnection region along open magnetic field lines.

Embodiments of systems and methods for compressing plasma are described in which plasma pressures above the breaking point of solid material can be achieved by injecting a plasma into a funnel of liquid metal in which the plasma is compressed and/or heated.

Embodiments of systems and methods for compressing plasma are described in which plasma pressures above the breaking point of solid material can be achieved by injecting a plasma into a funnel of liquid metal in which the plasma is compressed and/or heated.

Systems and methods utilizing successive, axially symmetric acceleration and adiabatic compression stages to heat and accelerate two compact tori towards each other and ultimately collide and compress the compact tori within a central chamber. Alternatively, systems and methods utilizing successive, axially asymmetric acceleration and adiabatic compression stages to heat and accelerate a first compact toroid towards and position within a central chamber and to heat and accelerate a second compact toroid towards the central chamber and ultimately collide and merge the first and second compact toroids and compress the compact merge tori within the central chamber.

Systems and methods utilizing successive, axially symmetric acceleration and adiabatic compression stages to heat and accelerate two compact tori towards each other and ultimately collide and compress the compact tori within a central chamber. Alternatively, systems and methods utilizing successive, axially asymmetric acceleration and adiabatic compression stages to heat and accelerate a first compact toroid towards and position within a central chamber and to heat and accelerate a second compact toroid towards the central chamber and ultimately collide and merge the first and second compact toroids and compress the compact merge tori within the central chamber.

A hollow cathode apparatus includes an outer tubular dielectric barrier circumferentially surrounding an outer tubular surface of the cathode tube, the outer tubular dielectric barrier being composed of a barrier material which is electrically non-conductive. Also disclosed is a system comprising the hollow cathode apparatus, an anode which is spaced from the output end of the tubular cathode, and electrical circuitry connected between the cathode tube and the anode for connection to a source of electrical power for providing an electrical potential between the cathode and anode to cause an electric current to pass from the emitter into the input gas to form a plasma which is then output through the output end of the cathode tube to form a plasma plume. The electrical circuitry comprises: a first power supply for connecting the cathode and the cathode electrode to a first source of DC power in an ignition power mode, wherein the first power supply comprises a current control device which is adapted to control the current between the cathode and the cathode electrode, wherein the current control device is arranged to function as an anti-surge current stabiliser; and a second power supply for connecting the anode and the cathode to a second source of DC power in a steady state power mode.