Abstract: An electrospray thruster including an emitter, an extractor, a propellant storage vessel for a primary liquid propellant, a propellant delivery pathway from the vessel to the emitter, and an ionic liquid. The ionic liquid is configured to have a solid phase at temperatures less than a predetermined temperature and a liquid phase at temperatures greater than the predetermined temperature, and the ionic liquid is configured to create a propellant isolation barrier in the solid phase to prevent absorption by the primary liquid propellant. The electrospray thruster also includes a heater associated with the vessel and configured to heat the ionic liquid to above the predetermined temperature for mixing with the primary liquid propellant.

Abstract: A satellite system and method features one or more electric propulsion thrusters optimized to have a specific impulse for station keeping and connected to a propellant tank for ionizing a propellant during station keeping maneuvers and receiving power from a solar photovoltaic array via a power management and distribution system during station keeping maneuvers; one or more electric propulsion thrusters are optimized to have a thrust for orbit raising and are connected to the propellant tank for ionizing the propellant during orbit raising maneuvers and receiving power directly from the solar photovoltaic array during orbit raising maneuvers or from the power management and distribution system

Abstract: An electrospray thruster and method includes an emitter, an extractor, and a propellant storage vessel. A porous propellant delivery pathway from the vessel to the emitter wicks liquid propellant to the emitter. An ionic liquid in the vessel has a chemical composition rending the ionic liquid solid at room temperature to prevent water absorption. In the liquid state, the ionic liquid exhibits favorable electrospray characteristics. A heater associated with the vessel is configured to heat the ionic liquid to above its melting point when thrust is required for delivery to the emitter via the porous propellant delivery pathway.

Abstract: A thruster includes a reactor including bundled metal elongate members therein configured to disassociate an introduced propellant flowing between the members, a combustor for combusting products of the disassociation, and a nozzle downstream of the combustor.

Abstract: A propellant isolation barrier including an ionic liquid is configured to have a solid phase at temperatures less than a predetermined temperature and a liquid phase at temperatures greater than the predetermined temperature. The ionic liquid is configured to create a propellant isolation barrier in the solid phase, mix with a primary liquid propellant in the liquid phase, and remain in the liquid phase and miscible with the primary liquid propellant at temperatures greater than and less than the predetermined temperature when mixed with the primary propellant.

Abstract: A gas production and utilization system includes an ionic liquid having an electrochemical window and engineered to produce a specific gas. A power supply is configured to apply a voltage potential across electrodes disposed in the ionic liquid at a level higher than the electrochemical window of the ionic liquid to decompose the ionic liquid. The resultant gas is delivered to a pressure vessel and may be utilized in a variety of different ways.

Abstract: A thruster includes a reactor including bundled metal elongate members therein configured to disassociate an introduced propellant flowing between the members, a combustor for combusting products of the disassociation, and a nozzle downstream of the combustor.

Abstract: A liquid degasser for a space device including a gas permeable material configured for contact with a flow of liquid to be de-gassed on one side and a vacuum on the other side, and wherein the gas permeable material allows gas in the liquid to diffuse to the vacuum to remove the gas from the liquid.

Abstract: A multi-functional power supply system for a Hall thruster including a thruster assembly for providing a plasma discharge and a cathode assembly for providing electrons. The cathode assembly includes an emitter, a keeper with a current limiting device, and a heater. A magnetic field source is operatively associated with the cathode assembly for generating a magnetic field to control the discharge. A plasma discharge circuit creates a plasma and accelerates the plasma to produce thrust. A power supply is connected to the keeper and the plasma discharge circuit and is connected to the heater through a switching device responsive to a predetermined condition for interrupting the power to the heater and simultaneously enabling the power supply to deliver power to the keeper and the plasma discharge circuit to initiate production of thrust.

Abstract: A multi-functional power supply system for a Hall thruster including a thruster assembly for providing a plasma discharge and a cathode assembly for providing electrons. The cathode assembly includes an emitter, a keeper with a current limiting device, and a heater. A magnetic field source is operatively associated with the cathode assembly for generating a magnetic field to control the discharge. A plasma discharge circuit creates a plasma and accelerates the plasma to produce thrust. A power supply is connected to the keeper and the plasma discharge circuit and is connected to the heater through a switching device responsive to a predetermined condition for interrupting the power to the heater and simultaneously enabling the power supply to deliver power to the keeper and the plasma discharge circuit to initiate production of thrust.

Abstract: A Hall thruster with a shared magnetic structure including a plurality of plasma accelerators each including an anode and a discharge zone for providing plasma discharge. An electrical circuit having one or more cathodes connected to the plurality of plasma accelerators emits electrons that are attracted to the anode in each of the plasma accelerators. A shared magnetic circuit structure establishes a transverse magnetic field in each of the plurality of plasma accelerators that creates an impedance to the flow of electrons toward the anode in each of the plurality of plasma accelerators and enables ionization of a gas moving through one or more of the plurality of plasma accelerators. The impedance localizes an axial electric field in the plurality of plasma accelerators for accelerating ionized gas through the one or more of the plurality of plasma accelerators to create thrust.

Abstract: A pulsed Hall thruster system includes a Hall thruster having an electron source, a magnetic circuit, and a discharge chamber; a power processing unit for firing the Hall thruster to generate a discharge; a propellant storage and delivery system for providing propellant to the discharge chamber and a control unit for defining a pulse duration &tgr;<0.1d3&rgr;/{dot over (m)}, where d is the characteristic size of the thruster, &rgr; is the propellant density at standard conditions, and {dot over (m)} is the propellant mass flow rate for operating either the power processing unit to provide to the Hall thruster a power pulse of a pre-selected duration, &tgr;, or operating the propellant storage and delivery system to provide a propellant flow pulse of duration, &tgr;, or providing both as pulses, synchronized to arrive coincidentally at the discharge chamber to enable the Hall thruster to produce a discreet output impulse.

Abstract: A pulsed Hall thruster system includes a Hall thruster having an electron source, a magnetic circuit, and a discharge chamber; a power processing unit for firing the Hall thruster to generate a discharge; a propellant storage and delivery system for providing propellant to the discharge chamber and a control unit for defining a pulse duration &tgr;<0.1d3&rgr;/{dot over (m)}, where d is the characteristic size of the thruster, &rgr; is the propellant density at standard conditions, and {dot over (m)} is the propellant mass flow rate for operating either the power processing unit to provide to the Hall thruster a power pulse of a pre-selected duration, &tgr;, or operating the propellant storage and delivery system to provide a propellant flow pulse of duration, &tgr;, or providing both as pulses, synchronized to arrive coincidentally at the discharge chamber to enable the Hall thruster to produce a discreet output impulse.

Abstract: A tandem Hall field plasma accelerator with closed electron drift includes a magnetic circuit having an inner pole and an outer pole and a magnetic field source and a discharge cavity disposed axially in tandem; the discharge cavity including an axially extending accelerator section defining an exit aperture between the inner and outer poles and a plenum section extending radially outwardly and upstream of the accelerator section and including an anode and a propellant injector. Also disclosed is the use of an electromagnetic coil which provides a magnetic field in a magnetic circuit and includes a multiple turn winding wound on an electrically conductive bobbin. The plasma discharge is connected electrically in series with the electromagnetic coil and a power source with a bobbin defining a single turn secondary coil winding on the magnetic circuit which reduces magnetic field fluctuations in the plasma discharge and reduces eddy currents and consequent heating of the magnetic circuit.

Abstract: A Hall field plasma accelerator with closed electron drift includes a composite anode including a housing with inner and outer walls which form an outer anode and an inner anode forming inner and outer distribution zones; the housing is electrically conductive and has an upstream end and an exit port electrically insulated from the housing; the composite anode includes an input distribution system for introducing plasma gas into the distribution zones; poles establish a magnetic field across the exit port and a cathode establishes an electron flow through the magnetic field toward the composite anode and creates an electric field through the exit port; the electrons ionize the plasma gas that is accelerated by the electric field through the exit port.