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RF Resonant Cavity Thruster
The EmDrive is a concept for a thruster for spacecraft, first written about in 2001. It is purported to generate thrust by reflecting microwaves inside the device, in a way that would violate the law of conservation of momentum and other laws of physics. The concept has been referred to at times as a resonant cavity thruster or as the latest Impossible Drive. There is no official design for this device. Neither person who claims to have invented it has committed to an explanation for how it could operate as a thruster or what elements define it, making it hard to say definitively whether a given object is an example of an EmDrive. However, over the years, prototypes based on its public descriptions have been constructed and tested. In 2016, Harold White's group at NASA observed a small apparent thrust from one such test, however subsequent studies suggested this was a measurement error caused by thermal gradients. In 2021, Martin Tajmar's group at the Dresden University of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Spacecraft Propulsion
Spacecraft propulsion is any method used to accelerate spacecraft and artificial satellites. In-space propulsion exclusively deals with propulsion systems used in the vacuum of space and should not be confused with space launch or atmospheric entry. Several methods of pragmatic spacecraft propulsion have been developed each having its own drawbacks and advantages. Most satellites have simple reliable chemical thrusters (often monopropellant rockets) or resistojet rockets for orbital station-keeping and some use momentum wheels for attitude control. Soviet bloc satellites have used electric propulsion for decades, and newer Western geo-orbiting spacecraft are starting to use them for north–south station-keeping and orbit raising. Interplanetary vehicles mostly use chemical rockets as well, although a few have used ion thrusters and Hall-effect thrusters (two different types of electric propulsion) to great success. Hypothetical in-space propulsion technologies describe the p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Conservation Of Momentum
In Newtonian mechanics, momentum (more specifically linear momentum or translational momentum) is the product of the mass and velocity of an object. It is a vector quantity, possessing a magnitude and a direction. If is an object's mass and is its velocity (also a vector quantity), then the object's momentum is : \mathbf = m \mathbf. In the International System of Units (SI), the unit of measurement of momentum is the kilogram metre per second (kg⋅m/s), which is equivalent to the newton-second. Newton's second law of motion states that the rate of change of a body's momentum is equal to the net force acting on it. Momentum depends on the frame of reference, but in any inertial frame it is a ''conserved'' quantity, meaning that if a closed system is not affected by external forces, its total linear momentum does not change. Momentum is also conserved in special relativity (with a modified formula) and, in a modified form, in electrodynamics, quantum mechanics, qu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Greg Egan
Greg Egan (born 20 August 1961) is an Australian science fiction writer and amateur mathematician, best known for his works of hard science fiction. Egan has won multiple awards including the John W. Campbell Memorial Award, the Hugo Award, and the Locus Award. Life and work Egan holds a Bachelor of Science degree in Mathematics from the University of Western Australia. He published his first work in 1983. He specialises in hard science fiction stories with mathematical and quantum ontology themes, including the nature of consciousness. Other themes include genetics, simulated reality, posthumanism, mind uploading, sexuality, artificial intelligence, and the superiority of rational naturalism to religion. He often deals with complex technical material, like new physics and epistemology. He is a Hugo Award winner (with eight other works shortlisted for the Hugos) and has also won the John W. Campbell Memorial Award for Best Science Fiction Novel. His early stories feature s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of California, Riverside
The University of California, Riverside (UCR or UC Riverside) is a public land-grant research university in Riverside, California. It is one of the ten campuses of the University of California system. The main campus sits on in a suburban district of Riverside with a branch campus of in Palm Desert. In 1907, the predecessor to UCR was founded as the UC Citrus Experiment Station, Riverside which pioneered research in biological pest control and the use of growth regulators responsible for extending the citrus growing season in California from four to nine months. Some of the world's most important research collections on citrus diversity and entomology, as well as science fiction and photography, are located at Riverside. UCR's undergraduate College of Letters and Science opened in 1954. The Regents of the University of California declared UCR a general campus of the system in 1959, and graduate students were admitted in 1961. To accommodate an enrollment of 21,000 stud ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John C
John is a common English name and surname: * John (given name) * John (surname) John may also refer to: New Testament Works * Gospel of John, a title often shortened to John * First Epistle of John, often shortened to 1 John * Second Epistle of John, often shortened to 2 John * Third Epistle of John, often shortened to 3 John People * John the Baptist (died c. AD 30), regarded as a prophet and the forerunner of Jesus Christ * John the Apostle (lived c. AD 30), one of the twelve apostles of Jesus * John the Evangelist, assigned author of the Fourth Gospel, once identified with the Apostle * John of Patmos, also known as John the Divine or John the Revelator, the author of the Book of Revelation, once identified with the Apostle * John the Presbyter, a figure either identified with or distinguished from the Apostle, the Evangelist and John of Patmos Other people with the given name Religious figures * John, father of Andrew the Apostle and Saint Peter * Pope Jo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
New Scientist
''New Scientist'' is a magazine covering all aspects of science and technology. Based in London, it publishes weekly English-language editions in the United Kingdom, the United States and Australia. An editorially separate organisation publishes a monthly Dutch-language edition. First published on 22 November 1956, ''New Scientist'' has been available in online form since 1996. Sold in retail outlets (paper edition) and on subscription (paper and/or online), the magazine covers news, features, reviews and commentary on science, technology and their implications. ''New Scientist'' also publishes speculative articles, ranging from the technical to the philosophical. ''New Scientist'' was acquired by Daily Mail and General Trust (DMGT) in March 2021. History Ownership The magazine was founded in 1956 by Tom Margerison, Max Raison and Nicholas Harrison as ''The New Scientist'', with Issue 1 on 22 November 1956, priced at one shilling (a twentieth of a pound in pre-decimal UK cu ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
China Academy Of Space Technology
The China Academy of Space Technology (CAST) () is a Chinese space agency and subordinate of China Aerospace Science and Technology Corporation (CASC). The agency was founded on 20 February 1968, and is the main spacecraft development and production facility in China. On 24 April 1970, CAST successfully launched China's first artificial satellite Dong Fang Hong I. Space flight programmes CAST designs and manufactures the Dong Fang Hong satellites. U.S. sanctions CAST is the majority shareholder of listed company China Spacesat. On 30 June, 2020, CAST owns 51.46% of China Spacesat Co. In August 2020, the United States Department of Defense published the names of companies linked to the People's Liberation Army operating directly or indirectly in the United States. China Spacesat Co. was included on the list. In November 2020, Donald Trump issued an executive order prohibiting any American company or individual from owning shares in companies that the United States Departme ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
American Institute Of Aeronautics And Astronautics
The American Institute of Aeronautics and Astronautics (AIAA) is a professional society for the field of aerospace engineering. The AIAA is the U.S. representative on the International Astronautical Federation and the International Council of the Aeronautical Sciences. In 2015, it had more than 30,000 members among aerospace professionals worldwide (a majority are American and/or live in the United States). History The AIAA was founded in 1963 from the merger of two earlier societies: the American Rocket Society (ARS), founded in 1930 as the American Interplanetary Society (AIS), and the Institute of the Aerospace Sciences (IAS), founded in 1932 as the Institute of the Aeronautical Sciences. Paul Johnston was the first executive director of the organization. Jim Harford took his seat after 18 months. The newly-formed structure gathered 47 technical committees and one broad technical publication, the ''AIAA Journal''. The ''AIAA Student Journal'' was also launched in 1963. T ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Journal Of Propulsion And Power
The ''Journal of Propulsion and Power'' is a bimonthly peer-reviewed scientific journal covering research on aerospace propulsion and power. The editor-in-chief is Joseph M. Powers (University of Notre Dame). It is published by the American Institute of Aeronautics and Astronautics and was established in 1985. Abstracting and indexing The journal is abstracted and indexed in: According to the ''Journal Citation Reports'', the journal has a 2018 impact factor of 1.362. See also References External links *{{Official website, https://arc.aiaa.org/journal/jpp English-language journals Engineering journals Publications established in 1985 Bimonthly journals Academic journals published by learned and professional societies ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Advanced Propulsion Physics Laboratory
The Advanced Propulsion Physics Laboratory or "Eagleworks Laboratories" at NASA's Johnson Space Center is a small research group investigating a variety of theories regarding new forms of spacecraft propulsion. The principal investigator is Dr. Harold G. White. The group is developing the White–Juday warp-field interferometer in the hope of observing small disturbances of spacetime and also testing small prototypes of thrusters that do not use reaction mass, with currently inconclusive results. The proposed principle of operation of these quantum vacuum plasma thrusters, such as the RF resonant cavity thruster ('EM Drive'), has been shown to be inconsistent with known laws of physics, including conservation of momentum and conservation of energy. No plausible theory of operation for such drives has been proposed. Purpose The Advanced Propulsion Physics Laboratory is enabled by section 2.3.7 of the NASA Technology Roadmap TA 2: In Space Propulsion Technologies: The lab' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wired (magazine)
''Wired'' (stylized as ''WIRED'') is a monthly American magazine, published in print and online editions, that focuses on how emerging technologies affect culture, the economy, and politics. Owned by Condé Nast, it is headquartered in San Francisco, California, and has been in publication since March/April 1993. Several spin-offs have been launched, including '' Wired UK'', ''Wired Italia'', ''Wired Japan'', and ''Wired Germany''. From its beginning, the strongest influence on the magazine's editorial outlook came from founding editor and publisher Louis Rossetto. With founding creative director John Plunkett, Rossetto in 1991 assembled a 12-page prototype, nearly all of whose ideas were realized in the magazine's first several issues. In its earliest colophons, ''Wired'' credited Canadian media theorist Marshall McLuhan as its "patron saint". ''Wired'' went on to chronicle the evolution of digital technology and its impact on society. ''Wired'' quickly became recognized ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Northwestern Polytechnical University
Northwestern Polytechnical University (NWPU; ) is a national key public research university in Xi'an, China. The university is funded by the Ministry of Industry and Information Technology. The university is a Chinese national Class A Double First Class University. It is also a member of the former Project 985 and Project 211. NPU specializes in education and research in the fields of aeronautical, astronautical and marine engineering. As of 2012, NPU had 13,736 graduate students (3,063 full-time doctorate candidates, 7,087 master candidates, 3,586 professional degree candidates) and 14,395 undergraduate students. As of 2021, Northwestern Polytechnical University was listed as one of the top 450 universities in both the Academic Ranking of World Universities and the U.S. News & World Report Best Global University Ranking. History NPU builds upon the legacies of its three major predecessors. Northwestern Engineering Institute In 1938, due to the Japanese invasion of China ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
