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Plasma Propulsion Engine
A plasma propulsion engine is a type of electric propulsion that generates thrust from a quasi-neutral Plasma (physics), plasma. This is in contrast with ion thruster engines, which generate thrust through extracting an ion current from the Plasma (physics), plasma source, which is then accelerated to high velocities using grids of anodes. These exist in many forms (see electric propulsion). However, in the scientific literature, the term "plasma thruster" sometimes encompasses thrusters usually designated as "Ion thruster, ion engines". Plasma thrusters do not typically use high voltage grids or anodes/cathodes to accelerate the charged particles in the plasma, but rather use currents and potentials that are generated internally to accelerate the ions, resulting in a lower exhaust velocity given the lack of high accelerating voltages. This type of thruster has a number of advantages. The lack of high voltage grids of anodes removes a possible limiting element as a result of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Urine
Urine is a liquid by-product of metabolism in humans and many other animals. In placental mammals, urine flows from the Kidney (vertebrates), kidneys through the ureters to the urinary bladder and exits the urethra through the penile meatus (males) or urethral meatus of the vulva (females) during urination. In other vertebrates, urine is excreted through the cloaca. Urine contains water-soluble by-products of Cell (biology), cellular metabolism that are rich in nitrogen and must be clearance (medicine), cleared from the Circulatory system, bloodstream, such as urea, uric acid and creatinine. A urinalysis can detect nitrogenous wastes of the mammalian body. Urine plays an important role in the earth's nitrogen cycle. In balanced ecosystems, urine fertilizes the soil and thus helps plants to grow. Therefore, Reuse of excreta, urine can be used as a fertilizer. Some animals use it to territory (animal)#Scent marking, mark their territories. Historically, aged or fermented urine (kn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wuhan University
Wuhan University (WHU; 武汉大学) is a key comprehensive public university in Wuhan, Hubei, China. It is directly affiliated with and funded by the Ministry of Education of the People's Republic of China, Ministry of Education of China. The university is part of Project 985, Project 211, and a pioneer in the Double First-Class Construction initiative. History The university's origins trace back to 1893 with the establishment of Ziqiang Institute by Zhang Zhidong, the then governor of Hubei and Hunan provinces during the late Qing Dynasty (1644-1911). In 1926, National Wuchang University, National Wuchang University of Commerce, Hubei Provincial Medical University, Hubei Provincial University of Legislation, Hubei Provincial University of Liberal Arts, and the private Wuchang Zhonghua University were merged into National Wuchang Sun Yat-sen University (also known as National Second Sun Yat-sen University). The school has an undergraduate department and 6 subjects including libe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
TacSat-2
TacSat-2 is the first in a series of U.S. military experimental technology and communication satellites.TacSat-2 (also known as JWS-D1 ((Joint Warfighting Space-Demonstrator 1) or RoadRunner) was an experimental satellite built by the USAF's Air Force Research Laboratory with an operational life expected to be not more than one year as part of the "Advanced Concept Technology Demonstration" program. Purpose The TacSat series of experimental spacecraft are designed to allow military commanders on a battlefield to request and obtain imagery and other data from a satellite as it passes overhead. Collected data will be delivered to field commanders in minutes rather than hours or days. The sensor on TacSat-2 could collect color images sharp enough to distinguish ground objects as small as 1 meter in diameter. Systems Satellites in the TacSat series were planned to use commercial or available launchers, and largely off-the-shelf components, in order to reduce costs. Satellite ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Hall-effect Thruster
In spacecraft propulsion, a Hall-effect thruster (HET) is a type of ion thruster in which the propellant is accelerated by an electric field. Hall-effect thrusters (based on the discovery by Edwin Hall) are sometimes referred to as Hall thrusters or Hall-current thrusters. Hall effect, Hall-effect thrusters use a magnetic field to limit the electrons' axial motion and then use them to ionize propellant, efficiently accelerate the ions to produce thrust, and neutralize the ions in the plume. The Hall-effect thruster is classed as a moderate specific impulse (1,600s) space propulsion technology and has benefited from considerable theoretical and experimental research since the 1960s. Hall thrusters operate on a variety of propellants, the most common being xenon and krypton. Other propellants of interest include argon, bismuth, iodine, magnesium, zinc and adamantane. Hall thrusters are able to accelerate their exhaust to effective exhaust velocity, speeds between 10 and 80 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Busek
Busek Company Incorporated is an American spacecraft propulsion company that builds thrusters, electronics, and various systems for spacecraft. History Busek was founded in 1985 by Vlad Hruby in Natick, Massachusetts. Busek started as a laboratory outside of Boston, Massachusetts. Flight missions TacSat-2 The first US Hall thruster flown in space, Busek's BHT-200, was launched aboard the Air Force Research Laboratory's (AFRL) TacSat-2 satellite. The Busek thruster was part of the Microsatellite Propulsion Integration (MPI) Experiment and was integrated on TacSat-2 under the direction of the DoD Space Test Program. TacSat-2 launched on December 16, 2006 from the NASA Wallops Flight Facility. LISA Pathfinder The first electrospray thruster that made it to space was manufactured by Busek and launched aboard the European Space Agency's LISA Pathfinder satellite on December 3, 2015. The micro-newton colloid-style electric thruster was developed under contract with ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Probe
Uncrewed spacecraft or robotic spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input, such as remote control, or remote guidance. They may also be autonomous, in which they have a pre-programmed list of operations that will be executed unless otherwise instructed. A robotic spacecraft for scientific measurements is often called a space probe or space observatory. Many space missions are more suited to telerobotic rather than crewed operation, due to lower cost and risk factors. In addition, some planetary destinations such as Venus or the vicinity of Jupiter are too hostile for human survival, given current technology. Outer planets such as Saturn, Uranus, and Neptune are too distant to reach with current crewed spaceflight technology, so telerobotic probes are the only way to explore them. Telerobotics also allows exploration of regions that are vulnerable to contamination by Earth micro-organisms sinc ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Zond 2
Zond 2 was a Soviet space probe, a member of the Zond program, and was the sixth Soviet spacecraft to attempt a flyby of Mars. (See Exploration of Mars) It was launched on November 30, 1964 at 13:12 UTC onboard Molniya 8K78 launch vehicle from Baikonur Cosmodrome, Kazakhstan, USSR. The spacecraft was intended to survey Mars but lost communication before arrival. History Zond-2 carried a phototelevision camera of the same type later used to photograph the Moon on Zond 3. The camera system also included two ultraviolet spectrometers. As on Mars 1, an infrared spectrometer was installed to search for signs of methane on Mars. Zond 2 also carried six Pulsed Plasma Thrusters (PPT) that served as actuators of the attitude control system. They were the first PPTs successfully used on a spacecraft. The PPT propulsion system was tested for 70 minutes on the 14 December 1964 when the spacecraft was 4.2 million kilometers from Earth. Zond 2, a ''Mars 3MV-4A'' craft, was launched ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet Union, it dissolved in 1991. During its existence, it was the list of countries and dependencies by area, largest country by area, extending across Time in Russia, eleven time zones and sharing Geography of the Soviet Union#Borders and neighbors, borders with twelve countries, and the List of countries and dependencies by population, third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of Republics of the Soviet Union, national republics, the largest and most populous of which was the Russian SFSR. In practice, Government of the Soviet Union, its government and Economy of the Soviet Union, economy were Soviet-type economic planning, highly centralized. As a one-party state go ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Helicon Double Layer Thruster
The helicon double-layer thruster is a prototype electric spacecraft propulsion. It was created by Australian scientist Christine Charles, based on a technology invented by Professor Rod Boswell, both of the Australian National University. The design has been verified by the ESA, which is participating in its development. Theory of operation A helicon double-layer thruster (HDLT) is a type of plasma thruster, which ejects ionized gas at high velocity to provide thrust to a spacecraft. In this thruster design, gas is injected into a tubular chamber (the ''source tube'') with one open end. Radio frequency AC power (at 13.56 MHz in the prototype design) is coupled into a specially shaped antenna wrapped around the chamber. The electromagnetic wave emitted by the antenna causes the gas to break down and form a plasma. The antenna then excites a helicon wave in the plasma, which further heats the plasma. The device has a roughly constant magnetic field in the source tube ( ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Australian National University
The Australian National University (ANU) is a public university, public research university and member of the Group of Eight (Australian universities), Group of Eight, located in Canberra, the capital of Australia. Its main campus in Acton, Australian Capital Territory, Acton encompasses seven teaching and research colleges, in addition to several national academies and institutes. Established in 1946, ANU is the only university to have been created by the Parliament of Australia. It traces its origins to Canberra University College, which was established in 1929 and was integrated into ANU in 1960. ANU enrols 13,329 undergraduate and 11,021 postgraduate students and employs 4,517 staff. The university's endowment stood at A$1.8 billion as of 2018. ANU counts six List of Nobel laureates, Nobel laureates and 49 Rhodes Scholarship, Rhodes scholars among its List of Australian National University people, faculty and alumni. The university has educated the incumbent Governor-Gene ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
