The invention relates to a solid or liquid propellant (2) tank (1) for a thruster, the tank (1) comprising means for forming a gas (9) in the tank, the tank (1) having an opening (4) of surface area S for the extraction of a flow (20) of the propellant gas from the tank (1). According to the invention, the tank (1) comprises a propellant gas flow on-off control system comprising a grid (6) arranged opposite the opening (4) of the tank (1), a first thermal regulation system (11, 21) for heating the gas (9) in the tank and a second thermal regulation system (12, 22) for heating the grid (6), said grid (6) including holes of total surface area greater than the surface area S of the opening of the tank (1).

Provided are various spacecraft propulsion systems, and associated methods of operation. A spacecraft comprises an ion propulsion system and an ion blocker suspended from the spacecraft via one or more electrically insulated tethers. The ion propulsion system is configured to generate a first propulsive force by emitting a charged ion beam in a direction with an ion velocity vector comprising an ion vector component that is perpendicular to a magnetic field of a planet, such as Earth. The magnetic field causes the ion beam to curve toward the ion blocker at a trajectory such that ions within the ion beam are blocked by the ion blocker to generate a second propulsive force on the ion blocker. The ion blocker blocks the ions by contacting or deflecting the ions. The ion blocker is positioned approximately twice the gyroradius of the ion beam trajectory.

A thruster has a first stage and a second stage. The first stage is a plasma source that outputs a plasma. The second stage is an accelerator. In one embodiment, the second stage is a plasma accelerator that accelerates the plasma. In another embodiment, the second stage is an ion accelerator that accelerates the ions from the plasma.

Disclosed is a closed drift, narrow channel Hall thruster configured to operate at powers <30 W. The thruster includes a thruster body and a neutralizing cathode. The thruster body includes a magnetic circuit including a magnetic source and two magnetic poles, a metallic, annular thruster channel formed by the magnetic poles with a downstream channel width smaller than about 3 mm and an upstream channel width greater than the downstream channel width, an anode positioned at the channel's entry, and a gas distributor configured to release a propellant gas into the thruster channel. The magnetic circuit is configured to generate a magnetic field in the thruster channel for trapping electrons therein. The channel walls (the magnetic poles) are under bias potential. The anode and the cathode are configured to generate a substantially axial electric field in the thruster channel. In operation, propellant gas atoms ionized by trapped electrons in the thruster channel, accelerate axially, exiting via the channel's exit.

A method for providing optimized power balanced low thrust transfer orbits utilizing split thruster execution to minimize an electric orbit raising duration of an apparatus includes monitoring an electric power balance on the apparatus. The method also includes firing a first thruster in response to the apparatus exiting an eclipse and based on the electric power balance. The method additionally includes firing a second thruster at a predetermined time delay after firing the first thruster based on the electric power balance. The method additionally includes ending firing one of the first thruster or the second thruster after a predetermined time duration based on the electric power balance. The method further includes ending firing another of the first thruster or the second thruster in response to the apparatus entering a next eclipse.

A field emission propulsion system for a spacecraft includes a control unit, a propulsion assembly, and a plurality of extractor electrode voltage sources. The propulsion assembly comprises a plurality of field emission propulsion units having an ion source with a plurality of ion emitters and extractor electrodes associated with the ion emitters and disposed in a field arrangement. The plurality of extractor electrode voltage sources, each associated with the extractor electrodes to control the same, are controlled by the control unit using an individual extractor electrode voltage.

According to certain aspects, an electric-propulsion thruster is used as part of a base or platform which also includes a power converter, having a plurality of inductors and other electrical components, and a printed circuit board (PCB). The PCB includes a layer at which the other electrical components and printed circuit inductor traces, for the plurality of inductors, are secured. The electric-propulsion thruster includes a housing (e.g., as part of the base or platform) providing a cavity and having at least one structurally-rigid side wall along the cavity, where the PCB is integrated with the electric-propulsion thruster for a compact arrangement which can be used to propel the apparatus. Such a compact design might be used as an important part of thruster spacecraft architecture such as micro-satellites (e.g., CubeSats).

Provided are various spacecraft propulsion systems, and associated methods of operation. A spacecraft comprises an ion propulsion system and an ion blocker suspended from the spacecraft via one or more electrically insulated tethers. The ion propulsion system is configured to generate a first propulsive force by emitting a charged ion beam in a direction with an ion velocity vector comprising an ion vector component that is perpendicular to a magnetic field of a planet, such as Earth. The magnetic field causes the ion beam to curve toward the ion blocker at a trajectory such that ions within the ion beam are blocked by the ion blocker to generate a second propulsive force on the ion blocker. The ion blocker blocks the ions by contacting or deflecting the ions. The ion blocker is positioned approximately twice the gyroradius of the ion beam trajectory.

A propulsion unit (10) for a spacecraft is described. The propulsion unit (10) comprises a centrally arranged cathode (20), a concentric anode (30), an injection point (60) for injecting a propellant (50) between the central cathode (20) and the concentric anode (30), an acceleration coil system (100) and a vectoring coil system (110) for expelling a plasma plume (75) from a nozzle (115). A plurality of superconducting coils (120, 125) is arranged about the concentric anode (30) for creating a magnetic field (B) between the central cathode (20) and the concentric anode (30) and directing the plasma plume (65) from the nozzle (115).

A thruster has a first stage and a second stage. The first stage is a plasma source that outputs a plasma. The second stage is an accelerator. In one embodiment, the second stage is a plasma accelerator that accelerates the plasma. In another embodiment, the second stage is an ion accelerator that accelerates the ions from the plasma.