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You can help Wikipedia by introducing appropriate citations. An ion thruster (or ion drive), one of several types of spacecraft propulsion, uses beams of ions — electrically charged atoms or molecules— for propulsion. The precise method for accelerating the ions may vary, but all designs take advantage of the charge-to-mass ratio of ions to accelerate them to very high velocities using a high electric field. Ion thrusters are therefore able to achieve high specific impulse, reducing the amount of reaction mass required, but increasing the amount of power required compared to chemical rockets. Ion thrusters can deliver one order of magnitude greater propellant efficiency than traditional liquid fuel rocket engines, but are constrained to very low accelerations by the power/weight ratios of available power systems. Ion engine in operation (from Great Images in NASA) File links The following pages link to this file: Spacecraft propulsion Ion thruster User:Patrick/w Categories: NASA images ...
Ion engine in operation (from Great Images in NASA) File links The following pages link to this file: Spacecraft propulsion Ion thruster User:Patrick/w Categories: NASA images ...
A remote camera captures a close-up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is used to change the velocity of spacecraft and artificial satellites, or in short, to provide delta-v. ...
An ion is an atom or group of atoms that normally are electrically neutral and achieve their status as an ion by loss (or addition) of (an) electron(s). ...
Electric charge is a fundamental conserved property of some subatomic particles, which determines their electromagnetic interactions. ...
Unsolved problems in physics: What causes anything to have mass? Mass is a property of a physical object that quantifies the amount of matter and energy it is equivalent to. ...
The specific impulse (commonly abbreviated Isp) of a propulsion system is the impulse (change in momentum) per unit mass of propellant. ...
Working mass is a mass against which a system operates in order to produce acceleration. ...
In physics, power (symbol: P) is the rate at which work is performed. ...
A remote camera captures a close_up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is used to change the velocity of spacecraft and artificial satellites, or in short, to provide delta_v. ...
An order of magnitude is the class of scale or magnitude of any amount, where each class contains values of a fixed ratio to the class preceding it. ...
A propellant is a material that is used to move an object by applying a motive force. ...
Liquid fuels are those combustible or energy-generating molecules which can be harnessed to create mechanical energy, which in turn usually produces kinetic energy, and which also must take the shape of their container. ...
The first ion thrusters, known as Kaufman-type ion thrusters, were developed by Harold R. Kaufman, working for NASA in the 1960s, and were based on the Duoplasmatron. Harold R. Kaufman is an American physicist, noted for his development of ion beam thrusters for NASA during the 1950s and 60s. ...
NASA Insignia Listen to this article · (info) This audio file was created from an article revision dated 2005-09-01, and does not reflect subsequent edits to the article. ...
The 1960s decade refers to the years from January 1, 1960 to December 31, 1969, inclusive. ...
Duoplasmatron, an invention of Manfred von Ardenne, is a type of ion beam source. ...
Types of ion thruster
There are many types of ion thruster currently in development; some are currently in use, while others have not yet been installed in spacecraft. Some of the types of ion thruster are: Other forms of high-efficiency electric thruster have also been proposed; see spacecraft propulsion. The electrostatic ion thruster is a kind of design for ion thrusters (a kind of highly-efficient low-thrust spacecraft propulsion running on electrical power). ...
Field Emission Electric Propulsion (FEEP) is an advanced electrostatic propulsion concept, a form of ion thruster, that uses liquid metal (usually either cesium or indium) as a propellant. ...
2 kW Laboratory Hall Thruster in operation at the Princeton Plasma Physics Laboratory A Hall effect thruster is a type of ion thruster in which the propellant is accelerated by an electric field in a plasma discharge with a radial magnetic field. ...
The Helicon Double Layer Thruster is a prototype spacecraft propulsion engine. ...
The Electrodeless Plasma Thruster is a spacecraft propulsion engine. ...
Pulsed inductive thrusters or PITs as they are commonly abbreviated are a form of spacecraft propulsion that uses perpendicular electric and magnetic fields to accelerate a propellant. ...
Magneto-Plasmadynamic (MPD) thrusters are a form of electric Propulsion which use the Lorentz force (a force exerted on charged particles by magnetic and electrical fields in combination) to generate thrust. ...
VASIMR test bed The Variable specific impulse magnetoplasma rocket (VASIMR) is a hypothetical form of spacecraft propulsion that uses radio waves and magnetic fields to accelerate a propellant. ...
A remote camera captures a close-up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is used to change the velocity of spacecraft and artificial satellites, or in short, to provide delta-v. ...
General design
 A diagram of how an electrostatic ion engine works In the simplest design, an electrostatic ion thruster, a gas like argon, Mercury (element) or Xenon are ionized by exposure to electrons provided by a cathode filament. The ions are accelerated by passing them through highly charged grids. Electrons are also fired into the ion beam downstream of the grids as the positively charged ions leave the thruster. This keeps the spacecraft and the thruster beams neutral electrically. The acceleration uses up very little reaction mass (i.e., the specific impulse, or Isp, is very high). Image File history File links DS1_Ion_Engine_Diagram. ...
Image File history File links DS1_Ion_Engine_Diagram. ...
The electrostatic ion thruster is a kind of design for ion thrusters (a kind of highly-efficient low-thrust spacecraft propulsion running on electrical power). ...
General Name, Symbol, Number argon, Ar, 18 Chemical series noble gases Group, Period, Block 18, 3, p Appearance colorless Atomic mass 39. ...
General Name, Symbol, Number mercury, Hg, 80 Chemical series transition metals Group, Period, Block 12, 6, d Appearance silvery white Atomic mass 200. ...
General Name, Symbol, Number xenon, Xe, 54 Chemical series noble gases Group, Period, Block 18, 5, p Appearance colorless Atomic mass 131. ...
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Diagram of a copper cathode in a Daniells cell. ...
Filaments surrounding a solar flare, caused by the interaction of the plasma in the Suns atmopshere with its magnetic field. ...
The specific impulse (commonly abbreviated Isp) of a propulsion system is the impulse (change in momentum) per unit mass of propellant. ...
Energy usage A major consideration is the amount of energy or power required to run the thruster, partly to ionize the materials, but most especially to accelerate the ions to the extremely high speeds required to have any useful effect. Exhaust speeds of 30 km/s are not uncommon, which is far faster than the 3–4.5 km/s for chemical rockets. This makes for notably low propellant usage.
With ion thrusters, most of the energy is lost in the high speed exhaust and this affects the thrust levels. It turns out that the overall thrust obtained from a given amount of energy is inversely proportional to exhaust speed (since energy consumption per kilogram of propellant is proportional to exhaust velocity squared, but the thrust per kilogram of propellant is only proportional to exhaust speed [1]). Increasing the ion exhaust momentum by 10 times requires expending 100 times more electrical energy. This results in a tradeoff between specific impulse and thrust, with the two being inversely proportional to each other for any given power.
For an extreme example, an ion thruster using a particle accelerator can be designed to achieve an exhaust velocity approaching the speed of light. This could provide an ion propulsion specific impulse approaching 30,000,000 seconds, but this would inevitably give negligible thrust due to the low propellant flow. A 1960s single stage 2 MeV linear Van de Graaff accelerator, here opened for maintenance A particle accelerator is a device that uses electric fields to propel electrically charged particles to high speeds and magnetic fields to contain them. ...
The specific impulse (commonly abbreviated Isp) of a propulsion system is the impulse (change in momentum) per unit mass of propellant. ...
The exhaust velocity attained by ions when they are accelerated inside of an electric field can be calculated using the following equation:
Thrust In practice, with currently practical energy sources of perhaps a few tens of kilowatts, and given a not untypical Isp of 3000 seconds (30 kN·s/kg), ion thrusters give only extremely modest forces (often tenths or hundredths of a newton). Large ion propulsion engines require large and massive electric power sources. Ion engines typically provide space craft acceleration rates of from 10-5 g to 10-3 g (0.000098 m/s2 to 0.0098 m/s2). Only nuclear power can deliver energy of gigawatts over weeks, months, or years. Together with a particle accelerator, especially a linear accelerator, there is a good combination for transporting bigger masses. The newton (symbol: N) is the SI unit of force. ...
For other uses, see g force. ...
A nuclear power station. ...
A 1960s single stage 2 MeV linear Van de Graaff accelerator, here opened for maintenance A particle accelerator is a device that uses electric fields to propel electrically charged particles to high speeds and magnetic fields to contain them. ...
A Linear particle accelerator is an electrical device for the acceleration of subatomic particles. ...
Lifespan Given the low thrust, the life of the thruster becomes important. Ion thrusters have to be kept running a large part of the time to allow the milligee acceleration to gain a useful velocity.
In the simplest ion thruster design, an electrostatic ion thruster, the ions often hit the grids, which leads to erosion of the grids and their eventual failure. Smaller grids lower the chance of these accidental collisions, but decrease the amount of charge they can handle, and thus lower the thrust. The electrostatic ion thruster is a kind of design for ion thrusters (a kind of highly-efficient low-thrust spacecraft propulsion running on electrical power). ...
Missions Of all the electric thrusters, ion thrusters have been the most seriously considered commercially and academically in the quest for interplanetary missions and orbit raising maneuvers. Ion thrusters are seen as the best solution for these missions as they require very high Δv (the overall change in velocity, taken as a single value) that can be built up over long periods of time. An Interplanetary Mission is a voyage or trip through space involving more than one planet. ...
The Hall effect thruster is a type of ion thruster that has been used for decades for station keeping by the Soviet Union and is now also applied in the West: the European Space Agency's satellite Smart 1 used it. This satellite completed its mission on September 3, 2006, in a controlled collision on the Moon's surface, after a trajectory deviation to be able to see the 3 meter crater the impact created on the visible side of the moon. 2 kW Laboratory Hall Thruster in operation at the Princeton Plasma Physics Laboratory A Hall effect thruster is a type of ion thruster in which the propellant is accelerated by an electric field in a plasma discharge with a radial magnetic field. ...
Station keeping is the practice of maintaining the orbital position of satellites in geostationary orbit. ...
The European Space Agency (ESA), established in 1975, is an inter-governmental organization dedicated to the exploration of space, currently with 17 member states. ...
SMART-1 was a Swedish-designed European Space Agency satellite that orbited around the Moon. ...
Bulk silicate composition (estimated wt%) SiO2 44. ...
NASA has developed an ion thruster called NSTAR for use in their interplanetary missions. This thruster was tested in the highly successful space probe Deep Space 1. Hughes has developed the XIPS (Xenon Ion Propulsion System) for performing stationkeeping on geosynchronous satellites. These are electrostatic ion thrusters and work by a different principle than Hall effect thrusters. NASA Insignia Listen to this article · (info) This audio file was created from an article revision dated 2005-09-01, and does not reflect subsequent edits to the article. ...
NSTAR is a private utility company that provides retail electricity and natural gas to customers in eastern and central Massachusetts. ...
The spacecraft Deep Space 1 was launched October 24, 1998 on top of a Delta II rocket. ...
Hughes logo adopted after his death Hughes developed the AIM-120 AMRAAM, one of the worlds most advanced air-to-air missiles Hughes Aircraft Company was a major defense/aerospace company founded by Howard Hughes. ...
A geosynchronous satellite is a satellite whose orbital track on the Earth repeats regularly over points on the Earth over time. ...
The electrostatic ion thruster is a kind of design for ion thrusters (a kind of highly-efficient low-thrust spacecraft propulsion running on electrical power). ...
In 2003 NASA ground-tested a new version of their ion thruster called High Power Electric Propulsion, or HiPEP. The HiPEP thruster differs from earlier ion thrusters because the xenon ions are produced using a combination of microwave energy and magnetic fields. The ionization is achieved through a process called electron cyclotron resonance (ECR). In ECR, a uniform magnetic field is applied to a chamber holding xenon gas. The small number of free electrons present in the neutral gas orbit around the magnetic field lines at a fixed frequency called the cyclotron frequency. Microwave radiation is applied that is carefully tuned to this frequency, supplying energy to the electrons, which then ionize more xenon atoms through collisions. This process is a highly efficient means of creating a plasma in low density gases. Previously the electrons required were provided by a hollow cathode. HiPEP Beam Extraction Test In 2003 NASA ground-tested a new version of their ion thruster called High Power Electric Propulsion, or HiPEP. Theory The HiPEP thruster differs from earlier ion thrusters because the xenon ions are produced using a combination of microwave and magnetic fields. ...
General Name, Symbol, Number xenon, Xe, 54 Chemical series noble gases Group, Period, Block 18, 5, p Appearance colorless Atomic mass 131. ...
{{otheruses4|the radiation|the appliance|microwaves equency = 1 GHz) to 1 mm (300 GHz). ...
To meet Wikipedias quality standards, this article may require cleanup. ...
Electron cyclotron resonance is a phenomenon observed both in plasma physics and condensed matter physics. ...
To meet Wikipedias quality standards, this article may require cleanup. ...
The Electron is a fundamental subatomic particle that carries an electric charge. ...
A pair of Dee electrodes with loops of coolant pipes on their surface at the Lawrence Hall of Science. ...
{{otheruses4|the radiation|the appliance|microwaves equency = 1 GHz) to 1 mm (300 GHz). ...
A Plasma lamp, illustrating some of the more complex phenomena of a plasma, including filamentation A solar coronal mass ejection blasts plasma throughout the solar system. ...
A gas is one of the five main phases of matter (after solid and liquid, and followed by plasma and Bose-Einstein Condensate) and, that subsequently appear as a solid material is subjected to increasingly higher temperatures. ...
Other propellants have been considered for use with ion thrusters. Research has been invested in fullerenes for this purpose, specifically C60 (buckminsterfullerene), due in part to its large electron-impact cross section. This property gives the potential for ion thrusters with higher efficiency than current Xenon-based designs at Isp values of less than 3,000 s (29 kN·s/kg). The fullerenes are a recently-discovered family of carbon allotropes named after Buckminster Fuller. ...
The Electron is a fundamental subatomic particle that carries an electric charge. ...
JP Aerospace has been working to build an orbital airship, which uses a combination of a balloon and ion thrusters to achieve orbit without any use of conventional rockets, for roughly 70 cents per ton per kilometer of altitude ($1/(short ton·mile)). The orbital airship, also called the space blimp, is a proposed space transportation system that carries payloads to and from low Earth orbit. ...
The word ton or tonne is derived from the Old English tunne, and ultimately from the Old French tonne, and referred originally to a large cask with a capacity of 252 wine gallons, which holds approximately 2100 pounds of water. ...
The Japanese space agency's Hayabusa, which was launched in 2003 and successfully rendezvoused with the asteroid 25143 Itokawa and remained in close proximity for many months to collect samples and information, is powered by two xenon Ion Engines. It is using xenon ions generated by microwave ECR, and a Carbon / Carbon-composite material for acceleration grid which is resistant to erosion.[2] For other uses, see Hayabusa (disambiguation). ...
Image:25143 Itokawa 051101-2 ISAS-JAXA.jpg Hayabusa image of 25143 Itokawa. ...
On 12 July 2001, the European Space Agency failed to launch their Artemis telecommunication satellite, and left it in a decaying orbit. The satellite's chemical propellant supply was sufficient to transfer it to a semi-stable orbit, and over then next 18 months the experimental onboard ion propulsion system (intended for secondary stationkeeping and maneuvering) was utilized to transfer it to a geostationary orbit. [3] The European Space Agency (ESA), established in 1975, is an inter-governmental organization dedicated to the exploration of space, currently with 17 member states. ...
See also A remote camera captures a close-up view of a Space Shuttle Main Engine during a test firing at the John C. Stennis Space Center in Hancock County, Mississippi Spacecraft propulsion is used to change the velocity of spacecraft and artificial satellites, or in short, to provide delta-v. ...
In a nuclear electric rocket, nuclear thermal energy is changed into electrical energy that is used to power one of the electrical propulsion technologies. ...
2 kW Laboratory Hall Thruster in operation at the Princeton Plasma Physics Laboratory A Hall effect thruster is a type of ion thruster in which the propellant is accelerated by an electric field in a plasma discharge with a radial magnetic field. ...
Magneto-Plasmadynamic (MPD) thrusters are a form of electric Propulsion which use the Lorentz force (a force exerted on charged particles by magnetic and electrical fields in combination) to generate thrust. ...
Field Emission Electric Propulsion (FEEP) is an advanced electrostatic propulsion concept, a form of ion thruster, that uses liquid metal (usually either cesium or indium) as a propellant. ...
Pulsed inductive thrusters or PITs as they are commonly abbreviated are a form of spacecraft propulsion that uses perpendicular electric and magnetic fields to accelerate a propellant. ...
VASIMR test bed Variable specific impulse magnetoplasma rockets or VASIMRs as the name is commonly abbreviated is a hypothetical form of spacecraft propulsion that uses radio waves and magnetic fields to accelerate a propellant. ...
The Electrodeless Plasma Thruster is a spacecraft propulsion engine. ...
This article is being considered for deletion in accordance with Wikipedias deletion policy. ...
References - ^ The energy computed from the rocket equation
- ^ ISAS. 小惑星探査機はやぶさ搭載イオンエンジン (Ion Engines used on Asteroid Probe Hayabusa) (Japanese). Retrieved on 2006-10-13.
- ^ ESA. Artemis team receives award for space rescue (English). Retrieved on 2006-11-16.
Tsiolkovskys rocket equation, named after Konstantin Tsiolkovsky who independently derived it, considers the principle of a rocket: a device that can apply an acceleration to itself (a thrust) by expelling part of its mass with high speed in the opposite direction, due to the conservation of momentum. ...
The Japan Aerospace eXploration Agency (JAXA) is Japans aerospace agency. ...
2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ...
October 13 is the 286th day of the year (287th in leap years) in the Gregorian calendar. ...
The European Space Agency (ESA), established in 1975, is an inter-governmental organization dedicated to the exploration of space, currently with 17 member states. ...
2006 (MMVI) is a common year starting on Sunday of the Gregorian calendar. ...
November 16 is the 320th day of the year (321st in leap years) in the Gregorian Calendar, with 45 days remaining. ...
External links - The NASA Glenn Research Center Ion Propulsion Group
- RMCybernetics - Propulsion using Ion Momentum Transfer
- Plasma Propulsion in Space
- Space Propulsion breakthrough
- Dual-Stage 4-Grid ESA press release
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