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25-499: The company builds gridded ion thrusters (NPT30) and cold gas thrusters (I2T5). ThrustMe was founded in 2017 by Ane Aanesland and Dmytro Rafalskyi, who previously worked at the École Polytechnique and CNRS as researchers in plasma physics and electric propulsion . Initially, the startup was incubated in Agoranov. Also in 2017, ThrustMe raised 1.7 million euros for its development. In 2018, ThrustMe received €2.4 million from

50-631: A longer lifetime than NSTAR. In 2006, Aerojet completed testing of a prototype NEXT ion thruster. Beginning in the 1970s, radio-frequency ion thrusters were developed at Giessen University and ArianeGroup . RIT-10 engines are flying on the EURECA and ARTEMIS . Qinetiq (UK) has developed the T5 and T6 engines (Kaufman type), used on the GOCE mission (T5) and the BepiColombo mission (T6). From Japan,

75-411: A magnetic torque assembly together with a nitrogen reaction control assembly (RCA). Data handling was carried out by EURECAs data handling subsystem (DHS) supported by telemetry and command subsystems providing the link to the ground station. EURECA consisted of 15 experiments: The WATCH instrument observed Cosmic X-rays in an extremely wide field of view, a 65 degree range capable of observing 1/4 of

100-493: A research article in the journal Nature , where the maneuvers described resulted in a cumulative altitude change above 3 km. According to the European Space Agency , in regard to the use of iodine rather than Xenon in a gridded ion thruster , "This small but potentially disruptive innovation could help to clear the skies of space junk, by enabling tiny satellites to self-destruct cheaply and easily at

125-466: Is responsible for extracting the charged propellant particles from the gas chamber. The second pair, operating at low voltage, provides the electrical field that accelerates the particles outwards, creating thrust. Other advantages to the new engine include a more compact design, allowing it to be scaled up to higher thrusts, and a narrower, less divergent exhaust plume of 3 degrees, which is reportedly five times narrower than previously achieved. This reduces

150-609: The European Commission to commercialise electric propulsion for nanosatellites. In 2019, Ane Aanesland received the CNRS innovation medal for her entrepreneurial activities. The same year, SpaceTy and ThrustMe maneuvered for the first time a satellite using iodine as propellant, with a cold-gas thruster. In 2021, ThrustMe, in partnership with SpaceTy, achieved the first in-orbit demonstration of an electric propulsion system powered by iodine. The results were published as

175-603: The European Space Agency , together with the Australian National University , announced successful testing of an improved electrostatic ion engine, the Dual-Stage 4-Grid (DS4G), that showed exhaust speeds of 210 km/s , reportedly four times higher than previously achieved, allowing for a specific impulse which is four times higher. Conventional electrostatic ion thrusters possess only two grids, one high voltage and one low voltage, which perform both

200-419: The accelerator grid prevents electrons of the beam plasma outside the thruster from streaming back to the discharge plasma. This can fail due to insufficient negative potential in the grid, which is a common ending for ion thrusters' operational life. The expelled ions propel the spacecraft in the opposite direction, according to Newton's 3rd law . Lower-energy electrons are emitted from a separate cathode, called

225-559: The demonstration in the 1960s and 70s, though, they were rarely used before the late 1990s. NASA Glenn continued to develop electrostatic gridded ion thrusters through the 1980s, developing the NASA Solar Technology Application Readiness (NSTAR) engine, that was used successfully on the Deep Space 1 probe, the first mission to fly an interplanetary trajectory using electric propulsion as

250-575: The early 1960s. The use of ion propulsion systems were first demonstrated in space by the NASA Lewis Space Electric Rocket Test (SERT) I and II. These thrusters used mercury as the reaction mass. The first was SERT-1 , launched July 20, 1964, which successfully proved that the technology operated as predicted in space. The second test, SERT-II, launched on February 3, 1970, verified the operation of two mercury ion engines for thousands of running hours. Despite

275-444: The electrostatic ion production method is the need for a cathode and power supply requirements. Electron bombardment thrusters require at the least, power supplies to the cathode, anode and chamber. RF and microwave types require an additional power supply to the rf generator, but no anode or cathode power supplies. The positively charged ions diffuse towards the chamber's extraction system (2 or 3 multi-aperture grids). After ions enter

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300-582: The end of their missions, by steering themselves into the atmosphere where they would burn up." Gridded ion thruster The gridded ion thruster is a common design for ion thrusters , a highly efficient low-thrust spacecraft propulsion method running on electrical power by using high-voltage grid electrodes to accelerate ions with electrostatic forces. The ion engine was first demonstrated by German-born NASA scientist Ernst Stuhlinger , and developed in practical form by Harold R. Kaufman at NASA Lewis (now Glenn) Research Center from 1957 to

325-425: The extraction grid systems, minor differences occur in the grid geometry and the materials used. This may have implications for the grid system operational lifetime. Electrostatic ion thrusters have also achieved a specific impulse of 30–100 kN·s/kg, or 3,000 to 10,000 s, better than most other ion thruster types. Electrostatic ion thrusters have accelerated ions to speeds reaching 100 km/s . In January 2006,

350-455: The ion extraction and acceleration functions. However, when the charge differential between these grids reaches around 5 kV, some of the particles extracted from the chamber collide with the low voltage grid, eroding it and compromising the engine's longevity. This limitation is successfully bypassed when two pairs of grids are used. The first pair operates at high voltage, possessing a voltage differential of around 3 kV between them; this grid pair

375-473: The neutralizer, into the ion beam to ensure that equal amounts of positive and negative charge are ejected. Neutralizing is needed to prevent the spacecraft from gaining a net negative charge, which would attract ions back toward the spacecraft and cancel the thrust. The ion optics are constantly bombarded by a small amount of secondary ions and erode or wear away, thus reducing engine efficiency and life. Several techniques were used to reduce erosion; most notable

400-416: The plasma sheath at a grid hole, they are accelerated by the potential difference between the first and second grids (called the screen and accelerator grids, respectively). The ions are guided through the extraction holes by the powerful electric field. The final ion energy is determined by the potential of the plasma, which generally is slightly greater than the screen grids' voltage. The negative voltage of

425-510: The primary propulsion. It later flew on the Dawn asteroid mission. Hughes Aircraft Company (now L-3 ETI) has developed the XIPS ( Xenon Ion Propulsion System ) for performing station keeping on its geosynchronous satellites (more than 100 engines flying). NASA is currently working on a 20–50 kW electrostatic ion thruster called HiPEP which will have higher efficiency, specific impulse , and

450-405: The propellant needed to correct the orientation of the spacecraft due to small uncertainties in the thrust vector direction. European Retrievable Carrier The European Retrievable Carrier ( EURECA ) was an uncrewed 4.5- tonne satellite with 15 experiments. It was a European Space Agency (ESA) mission and the acronym was derived from Archimedes ' bathtub revelation " Eureka! ". It

475-656: The sky. The design is a Rotation Modulation Collimator, in which stripes of NaI(Tl) and CsI(Na) detectors make a phoswich . WATCH monitored about 25 X-rays sources over the whole sky over the course of the mission, as well as detecting 19 cosmic gamma ray bursts. Many of the gamma ray bursts were able to be localized to within 1 degree. In the summer of 2016, EURECA was transported to the Swiss Federal Laboratories for Materials Science and Technology (Empa) in Dübendorf near Zurich where X-ray scans of

500-479: The μ10, using microwaves, flew on the Hayabusa mission. In 2021, DART launched carrying a NEXT-C xenon ion thruster. In 2021, ThrustMe reported satellite orbit changes using their NPT30-I2 iodine ion thruster. Propellant atoms are injected into the discharge chamber and are ionized, forming a plasma. There are several ways of producing the electrostatic ions for the discharge chamber: Related to

525-455: Was achieved by means of a freon cooling loop which dissipated the thermal load through two radiators into space. The passive system made use of multilayer insulation blankets combined with electrical heaters. The electrical subsystem was powered by deployable and retractable solar arrays together with four 40 amp-hour nickel-cadmium batteries . When EURECA was in the Shuttle cargo bay, power

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550-476: Was built by the German MBB -ERNO and had automatic material science cells as well as small telescopes for solar observation (including x-ray). It was launched 31 July 1992 by Space Shuttle Atlantis during STS-46 , and placed into an orbit at an altitude of 508 km (316 mi). EURECA was retrieved on 1 July 1993 by Space Shuttle Endeavour during STS-57 and returned to Earth. It

575-702: Was designed to fly five times with different experiments but the following flights were cancelled. EURECA is one of the few uncrewed space vehicles that have been returned to the Earth unharmed. It has been on display at the Swiss Museum of Transport in Lucerne since 2000. EURECA was made of high-strength carbon-fiber struts and titanium nodal points joined together to form a framework of cubic elements. Thermal control on EURECA combined both active and passive heat transfer and radiation systems. Active heat transfer

600-410: Was supplied by the Shuttle. The modular attitude and orbit control subsystem (AOCS) maintained attitude and spacecraft orientation and stabilization. An orbit transfer assembly, consisting of four thrusters, was used to boost EURECA to its operational attitude of 515 km (320 mi) and return it to a retrievable orbit of about 300 km (190 mi). EURECA was three-axis stabilized by means of

625-479: Was switching to a different propellant. Mercury or caesium atoms were used as propellants during tests in the 1960s and 1970s, but these propellants adhered to, and eroded the grids. Xenon atoms, on the other hand, are far less corrosive, and became the propellant of choice for virtually all ion thruster types. NASA has demonstrated continuous operation of NSTAR thruster for over 16,000 hours (1.8 years) and NEXT thruster for over 48,000 hours (5.5 years). In

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