|
Weightlessness
Weightlessness is the complete or near-complete absence of the sensation of weight. It is also termed zero gravity, zero G-force, or zero-G. Weight is a measurement of the force on an object at rest in a relatively strong gravitational field (such as on the surface of the Earth). These weight-sensations originate from contact with supporting floors, seats, beds, scales, and the like. A sensation of weight is also produced, even when the gravitational field is zero, when contact forces act upon and overcome a body's inertia by mechanical, non-gravitational forces- such as in a centrifuge, a rotating space station, or within an accelerating vehicle. When the gravitational field is non-uniform, a body in free fall experiences tidal effects and is not stress-free. Near a black hole, such tidal effects can be very strong. In the case of the Earth, the effects are minor, especially on objects of relatively small dimensions (such as the human body or a spacecraft) and the overa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Reduced-gravity Aircraft
A reduced-gravity aircraft is a type of fixed-wing aircraft that provides brief near-weightless environments for training astronauts, conducting research and making gravity-free movie shots. Versions of such airplanes were operated by the NASA Reduced Gravity Research Program, and one is currently operated by the Human Spaceflight and Robotic Exploration Programmes of the European Space Agency. The unofficial nickname "vomit comet" became popular among those who experienced their operation. History Parabolic flight as a way of simulating weightlessness was first proposed by the German aerospace engineer Fritz Haber and the German physicist Heinz Haber in 1950. Both had been brought to the US after World War II as part of Operation Paperclip. As well, Shih-Chun Wang studied nausea in astronauts for NASA, which helped lead to the creation of the vomit comet. Parabolic flights are sometimes used to examine the effects of weightlessness on a living organism. While humans are b ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microgravity
The term micro-g environment (also μg, often referred to by the term microgravity) is more or less synonymous with the terms ''weightlessness'' and ''zero-g'', but emphasising that g-forces are never exactly zero—just very small (on the International Space Station (ISS), for example, the small g-forces come from tidal effects, gravity from objects other than the Earth, such as astronauts, the spacecraft, and the Sun, air resistance, and astronaut movements that impart momentum to the space station). The symbol for microgravity, ''μg'', was used on the insignias of Space Shuttle flights STS-87 and STS-107, because these flights were devoted to microgravity research in low Earth orbit. The most commonly known microgravity environment can be found aboard the ISS which is located in low-earth orbit at an altitude of around 400 km, orbiting Earth approximately 15 times per day in what is considered free fall. The effects of free fall also enable the creation of short-du ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Weight
In science and engineering, the weight of an object is the force acting on the object due to gravity. Some standard textbooks define weight as a Euclidean vector, vector quantity, the gravitational force acting on the object. Others define weight as a scalar quantity, the magnitude of the gravitational force. Yet others define it as the magnitude of the reaction (physics), reaction force exerted on a body by mechanisms that counteract the effects of gravity: the weight is the quantity that is measured by, for example, a spring scale. Thus, in a state of free fall, the weight would be zero. In this sense of weight, terrestrial objects can be weightless: ignoring Drag (physics), air resistance, the famous apple falling from the tree, on its way to meet the ground near Isaac Newton, would be weightless. The unit of measurement for weight is that of force, which in the International System of Units (SI) is the newton (unit), newton. For example, an object with a mass of one kilogram ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-force
The gravitational force equivalent, or, more commonly, g-force, is a measurement of the type of force per unit mass – typically acceleration – that causes a perception of weight, with a g-force of 1 g (not gram in mass measurement) equal to the conventional value of gravitational acceleration on Earth, ''g'', of about . Since g-forces indirectly produce weight, any g-force can be described as a "weight per unit mass" (see the synonym specific weight). When the g-force is produced by the surface of one object being pushed by the surface of another object, the reaction force to this push produces an equal and opposite weight for every unit of each object's mass. The types of forces involved are transmitted through objects by interior mechanical stresses. Gravitational acceleration (except certain electromagnetic force influences) is the cause of an object's acceleration in relation to free fall. The g-force experienced by an object is due to the vector sum of all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Free Fall
In Newtonian physics, free fall is any motion of a body where gravity is the only force acting upon it. In the context of general relativity, where gravitation is reduced to a space-time curvature, a body in free fall has no force acting on it. An object in the technical sense of the term "free fall" may not necessarily be falling down in the usual sense of the term. An object moving upwards might not normally be considered to be falling, but if it is subject to only the force of gravity, it is said to be in free fall. The Moon is thus in free fall around the Earth, though its orbital speed keeps it in very far orbit from the Earth's surface. In a roughly uniform gravitational field gravity acts on each part of a body approximately equally. When there are no other forces, such as the normal force exerted between a body (e.g. an astronaut in orbit) and its surrounding objects, it will result in the sensation of weightlessness, a condition that also occurs when the gravitati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
G-force
The gravitational force equivalent, or, more commonly, g-force, is a measurement of the type of force per unit mass – typically acceleration – that causes a perception of weight, with a g-force of 1 g (not gram in mass measurement) equal to the conventional value of gravitational acceleration on Earth, ''g'', of about . Since g-forces indirectly produce weight, any g-force can be described as a "weight per unit mass" (see the synonym specific weight). When the g-force is produced by the surface of one object being pushed by the surface of another object, the reaction force to this push produces an equal and opposite weight for every unit of each object's mass. The types of forces involved are transmitted through objects by interior mechanical stresses. Gravitational acceleration (except certain electromagnetic force influences) is the cause of an object's acceleration in relation to free fall. The g-force experienced by an object is due to the vector sum of all ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
German Aerospace Center
The German Aerospace Center (german: Deutsches Zentrum für Luft- und Raumfahrt e.V., abbreviated DLR, literally ''German Center for Air- and Space-flight'') is the national center for aerospace, energy and transportation research of Germany, founded in 1969. It is headquartered in Cologne with 35 locations throughout Germany. The DLR is engaged in a wide range of research and development projects in national and international partnerships. DLR also acts as the German space agency and is responsible for planning and implementing the German space programme on behalf of the German federal government. As a project management agency, DLR coordinates and answers the technical and organisational implementation of projects funded by a number of German federal ministries. As of 2020, the German Aerospace Center had a national budget of €1.261 billion. Overview DLR has approximately 10.000 employees at 30 locations in Germany. Institutes and facilities are spread over 13 sites, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airbus A310
The Airbus A310 is a wide-body aircraft, designed and manufactured by Airbus Industrie, then a consortium of European aerospace manufacturers. Airbus had identified a demand for an aircraft smaller than the A300, the first twin-jet wide-body. On 7 July 1978, the A310 (initially the A300B10) was launched with orders from Swissair and Lufthansa. On 3 April 1982, the first prototype conducted its maiden flight, and the A310 received its type certification on 11 March 1983. Keeping the same eight-abreast cross-section, the A310 is shorter than the initial A300 variants, and has a smaller wing, down from . The A310 introduced a two-crew glass cockpit, later adopted for the A300-600 with a common type rating. It was powered by the same General Electric CF6-80 or Pratt & Whitney JT9D then PW4000 turbofan jet engines. It can seat 220 passengers in two classes, or 240 in all-economy, and has a flying range up to . It has overwing exits between the two main front and rear door pair ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gravity
In physics, gravity () is a fundamental interaction which causes mutual attraction between all things with mass or energy. Gravity is, by far, the weakest of the four fundamental interactions, approximately 1038 times weaker than the strong interaction, 1036 times weaker than the electromagnetic force and 1029 times weaker than the weak interaction. As a result, it has no significant influence at the level of subatomic particles. However, gravity is the most significant interaction between objects at the macroscopic scale, and it determines the motion of planets, stars, galaxies, and even light. On Earth, gravity gives weight to physical objects, and the Moon's gravity is responsible for sublunar tides in the oceans (the corresponding antipodal tide is caused by the inertia of the Earth and Moon orbiting one another). Gravity also has many important biological functions, helping to guide the growth of plants through the process of gravitropism and influencing the circ ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Station
A space station is a spacecraft capable of supporting a human crew in orbit for an extended period of time, and is therefore a type of space habitat. It lacks major propulsion or landing systems. An orbital station or an orbital space station is an artificial satellite (i.e. a type of orbital spaceflight). Stations must have docking ports to allow other spacecraft to dock to transfer crew and supplies. The purpose of maintaining an orbital outpost varies depending on the program. Space stations have most often been launched for scientific purposes, but military launches have also occurred. Space stations have harboured so far the only long-duration direct human presence in space. After the first station Salyut 1 (1971) and its tragic Soyuz 11 crew, space stations have been operated consecutively since Skylab (1973), having allowed a progression of long-duration direct human presence in space. Stations have been occupied by consecutive crews since 1987 with the Salyut successor M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
NASA
The National Aeronautics and Space Administration (NASA ) is an independent agency of the US federal government responsible for the civil space program, aeronautics research, and space research. NASA was established in 1958, succeeding the National Advisory Committee for Aeronautics (NACA), to give the U.S. space development effort a distinctly civilian orientation, emphasizing peaceful applications in space science. NASA has since led most American space exploration, including Project Mercury, Project Gemini, the 1968-1972 Apollo Moon landing missions, the Skylab space station, and the Space Shuttle. NASA supports the International Space Station and oversees the development of the Orion spacecraft and the Space Launch System for the crewed lunar Artemis program, Commercial Crew spacecraft, and the planned Lunar Gateway space station. The agency is also responsible for the Launch Services Program, which provides oversight of launch operations and countdown management f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CNES
The (CNES; French: ''Centre national d'études spatiales'') is the French government space agency (administratively, a "public administration with industrial and commercial purpose"). Its headquarters are located in central Paris and it is under the supervision of the French Ministries of Defence and Research. It operates from the Toulouse Space Centre and the Guiana Space Centre, but also has payloads launched from space centres operated by other countries. The president of CNES is Philippe Baptiste. CNES is a member of Institute of Space, its Applications and Technologies. It is Europe's largest and most important national organization of its type. History CNES was established under President Charles de Gaulle in 1961. It is the world's third oldest space agency, after the Soviet space program (Russia), and NASA (United States). CNES was responsible for the training of French astronauts, until the last active CNES astronauts transferred to the European Space Agency in 200 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
