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Kármán Line
The Kármán line (or von Kármán line ) is a conventional definition of the Outer space#Boundary, edge of space; it is widely but not universally accepted. The international record-keeping body Fédération Aéronautique Internationale, FAI (Fédération aéronautique internationale) defines the Kármán line at an altitude of above above mean sea level, mean sea level. While named after Theodore von Kármán, who calculated a theoretical limit of altitude for aeroplane flight at above Earth, the later established Kármán line is more general and has no distinct physical significance, in that there is a rather gradual difference between the characteristics of the atmosphere at the line, and experts disagree on defining a distinct boundary where the atmosphere ends and space begins. It lies well above the altitude reachable by conventional airplanes or high-altitude balloons, and is approximately where satellites, even on very eccentric trajectories, will Orbital decay, dec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
ISS043-E-143486 - View Of Earth
The International Space Station (ISS) is a large space station that was Assembly of the International Space Station, assembled and is maintained in low Earth orbit by a collaboration of five space agencies and their contractors: NASA (United States), Roscosmos (Russia), European Space Agency, ESA (Europe), JAXA (Japan), and Canadian Space Agency, CSA (Canada). As the largest space station ever constructed, it primarily serves as a platform for conducting scientific experiments in microgravity and studying the space environment. The station is divided into two main sections: the Russian Orbital Segment (ROS), developed by Roscosmos, and the US Orbital Segment (USOS), built by NASA, ESA, JAXA, and CSA. A striking feature of the ISS is the Integrated Truss Structure, which connect the station’s vast system of solar panels and Spacecraft thermal control, radiators to its pressurized modules. These modules support diverse functions, including scientific research, crew habitation, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Appleton-Century-Crofts
Appleton-Century-Crofts, Inc. was a division of the Meredith Publishing Company. It was a result of the merger of Appleton-Century Company with F.S. Crofts Co. in 1948. Prior to that The Century Company had merged with D. Appleton & Company in 1933. The Century Company and its subsequent incarnations published the '' New Century Dictionary''. Eventually Meredith sold the majority of the company and the Appleton name to Prentice-Hall in 1973. Part of the company became part of Hawthorn Books and New Win Publishing. Timeline * 1948 Appleton-Century Company, founded in 1933, merged with F. S. Crofts Co., founded in 1924, to form Appleton-Century-Crofts. * 1960 Purchased by Meredith Publishing Company * 1969 Meredith trade books division sold to Hawthorn Books * 1973 Appleton textbook division purchased by Prentice Hall; the medical division retains the Appleton name * 1974 New Century division sold to Charles Walther, and was later renamed New Win Publishing * 1998 Prenti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerodynamics
Aerodynamics () is the study of the motion of atmosphere of Earth, air, particularly when affected by a solid object, such as an airplane wing. It involves topics covered in the field of fluid dynamics and its subfield of gas dynamics, and is an important domain of study in aeronautics. The term ''aerodynamics'' is often used synonymously with gas dynamics, the difference being that "gas dynamics" applies to the study of the motion of all gases, and is not limited to air. The formal study of aerodynamics began in the modern sense in the eighteenth century, although observations of fundamental concepts such as aerodynamic drag were recorded much earlier. Most of the early efforts in aerodynamics were directed toward achieving Aircraft#Heavier-than-air – aerodynes, heavier-than-air flight, which was first demonstrated by Otto Lilienthal in 1891. Since then, the use of aerodynamics through mathematical analysis, empirical approximations, wind tunnel experimentation, and computer si ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kepler Problem
In classical mechanics, the Kepler problem is a special case of the two-body problem, in which the two bodies interact by a central force that varies in strength as the inverse square of the distance between them. The force may be either attractive or repulsive. The problem is to find the position or speed of the two bodies over time given their masses, positions, and velocities. Using classical mechanics, the solution can be expressed as a Kepler orbit using six orbital elements. The Kepler problem is named after Johannes Kepler, who proposed Kepler's laws of planetary motion (which are part of classical mechanics and solved the problem for the orbits of the planets) and investigated the types of forces that would result in orbits obeying those laws (called ''Kepler's inverse problem''). For a discussion of the Kepler problem specific to radial orbits, see Radial trajectory. General relativity provides more accurate solutions to the two-body problem, especially in stron ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aerodynamic Lift
When a fluid flows around an object, the fluid exerts a force on the object. Lift is the component of this force that is perpendicular to the oncoming flow direction. It contrasts with the drag force, which is the component of the force parallel to the flow direction. Lift conventionally acts in an upward direction in order to counter the force of gravity, but it is defined to act perpendicular to the flow and therefore can act in any direction. If the surrounding fluid is air, the force is called an aerodynamic force. In water or any other liquid, it is called a hydrodynamic force. Dynamic lift is distinguished from other kinds of lift in fluids. Aerostatic lift or buoyancy, in which an internal fluid is lighter than the surrounding fluid, does not require movement and is used by balloons, blimps, dirigibles, boats, and submarines. Planing lift, in which only the lower portion of the body is immersed in a liquid flow, is used by motorboats, surfboards, windsurfers, sailb ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bell X-2
The Bell X-2 (nicknamed "Starbuster") was an X-plane research aircraft built to investigate flight characteristics in the Mach 2–3 range. The X-2 was a rocket-powered, swept-wing research aircraft developed jointly in 1945 by Bell Aircraft Corporation, the United States Army Air Forces and the National Advisory Committee for Aeronautics (NACA) to explore aerodynamic problems of supersonic flight and to expand the speed and altitude regimes obtained with the earlier X-1 series of research aircraft. Design and development The Bell X-2 was developed to provide a vehicle for researching flight characteristics at speeds and altitudes in excess of the capabilities of the Bell X-1 and D-558 II, while investigating aerodynamic heating problems in what was then called the "thermal thicket". The Bell X-2 had a prolonged development period due to the advances needed in aerodynamic design, control systems, materials that retained adequate mechanical properties at high temperature, and ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Iven Carl Kincheloe Jr
Iven Carl "Kinch" Kincheloe Jr. (July 2, 1928 – July 26, 1958) was an American pilot. He served in the U.S. Air Force during the Korean War, in which he was recognized as a flying ace. He continued as a test pilot after the war, participating in the Bell X-2 program, in which he set an altitude record of in 1956. For this suborbital flight above most of the atmosphere, he became known as "The First Spaceman". He was selected for the Air Force's program to put a man in space, but was killed in a plane crash in 1958. Early life and education Born July 2, 1928, in Detroit, Michigan, Kincheloe grew up in Cassopolis, Michigan, Cassopolis in the West Michigan, southwest part of the state, the only child of Iven C. Kincheloe Sr. (1894–1966) and Frances Wilder Kincheloe. Interested in aviation from a very young age, he graduated from Dowagiac, Michigan, Dowagiac High School in 1945 and attended Purdue University in West Lafayette, Indiana. Kincheloe joined the Reserve Officers' Trai ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Airspace
Airspace is the portion of the atmosphere controlled by a country above its territory, including its territorial waters or, more generally, any specific three-dimensional portion of the atmosphere. It is not the same as outer space which is the expanse or space outside the Earth and aerospace which is the general term for Earth's atmosphere and the outer space within the planet's vicinity. Horizontal boundary By international law, a state "has complete and exclusive sovereignty over the airspace above its territory", which corresponds with the maritime definition of territorial waters as being 12 nautical miles (22.2 km) out from a nation's coastline. Airspace not within any country's territorial limit is considered international, analogous to the "high seas" in maritime law. However, a country may, by international agreement, assume responsibility for controlling parts of international airspace, such as those over the oceans. Such airspace in respect of which a countr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tide
Tides are the rise and fall of sea levels caused by the combined effects of the gravitational forces exerted by the Moon (and to a much lesser extent, the Sun) and are also caused by the Earth and Moon orbiting one another. Tide tables can be used for any given locale to find the predicted times and amplitude (or " tidal range"). The predictions are influenced by many factors including the alignment of the Sun and Moon, the phase and amplitude of the tide (pattern of tides in the deep ocean), the amphidromic systems of the oceans, and the shape of the coastline and near-shore bathymetry (see '' Timing''). They are however only predictions, the actual time and height of the tide is affected by wind and atmospheric pressure. Many shorelines experience semi-diurnal tides—two nearly equal high and low tides each day. Other locations have a diurnal tide—one high and low tide each day. A "mixed tide"—two uneven magnitude tides a day—is a third regular category. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Meander
A meander is one of a series of regular sinuous curves in the Channel (geography), channel of a river or other watercourse. It is produced as a watercourse erosion, erodes the sediments of an outer, concave bank (cut bank, cut bank or river cliff) and deposits sediments on an inner, convex bank which is typically a point bar. The result of this coupled erosion and sedimentation is the formation of a sinuous course as the channel migrates back and forth across the axis of a floodplain. The zone within which a meandering stream periodically shifts its channel is known as a meander belt. It typically ranges from 15 to 18 times the width of the channel. Over time, meanders migrate downstream, sometimes in such a short time as to create civil engineering challenges for local municipalities attempting to maintain stable roads and bridges.Neuendorf, K.K.E., J.P. Mehl Jr., and J.A. Jackson, J.A., eds. (2005) ''Glossary of Geology'' (5th ed.). Alexandria, Virginia, American Geological I ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mean Sea Level
A mean is a quantity representing the "center" of a collection of numbers and is intermediate to the extreme values of the set of numbers. There are several kinds of means (or "measures of central tendency") in mathematics, especially in statistics. Each attempts to summarize or typify a given group of data, illustrating the magnitude and sign of the data set. Which of these measures is most illuminating depends on what is being measured, and on context and purpose. The ''arithmetic mean'', also known as "arithmetic average", is the sum of the values divided by the number of values. The arithmetic mean of a set of numbers ''x''1, ''x''2, ..., x''n'' is typically denoted using an overhead bar, \bar. If the numbers are from observing a sample of a larger group, the arithmetic mean is termed the '' sample mean'' (\bar) to distinguish it from the group mean (or expected value) of the underlying distribution, denoted \mu or \mu_x. Outside probability and statistics, a wide rang ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
