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Artificial Gravity
Artificial gravity is the creation of an inertial force that mimics the effects of a gravitational force, usually by rotation. Artificial gravity, or rotational gravity, is thus the appearance of a centrifugal force in a rotating frame of reference (the transmission of centripetal acceleration via normal force in the non-rotating frame of reference), as opposed to the force experienced in linear acceleration, which by the equivalence principle is indistinguishable from gravity. In a more general sense, "artificial gravity" may also refer to the effect of linear acceleration, e.g. by means of a rocket engine. Rotational simulated gravity has been used in simulations to help astronauts train for extreme conditions. Rotational simulated gravity has been proposed as a solution in human spaceflight to the adverse health effects caused by prolonged weightlessness. However, there are no current practical outer space applications of artificial gravity for humans due to concerns ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Agena Target Docking Vehicle At A Distance Of Approximately 80 Feet From The Gemini-11 Spacecraft
''The'' is a grammatical article in English, denoting nouns that are already or about to be mentioned, under discussion, implied or otherwise presumed familiar to listeners, readers, or speakers. It is the definite article in English. ''The'' is the most frequently used word in the English language; studies and analyses of texts have found it to account for seven percent of all printed English-language words. It is derived from gendered articles in Old English which combined in Middle English and now has a single form used with nouns of any gender. The word can be used with both singular and plural nouns, and with a noun that starts with any letter. This is different from many other languages, which have different forms of the definite article for different genders or numbers. Pronunciation In most dialects, "the" is pronounced as (with the voiced dental fricative followed by a schwa) when followed by a consonant sound, and as (homophone of the archaic pronoun ''thee'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centripetal Force
Centripetal force (from Latin ''centrum'', "center" and ''petere'', "to seek") is the force that makes a body follow a curved trajectory, path. The direction of the centripetal force is always orthogonality, orthogonal to the motion of the body and towards the fixed point of the instantaneous osculating circle, center of curvature of the path. Isaac Newton coined the term, describing it as "a force by which bodies are drawn or impelled, or in any way tend, towards a point as to a centre". In Newtonian mechanics, gravity provides the centripetal force causing astronomical orbits. One common example involving centripetal force is the case in which a body moves with uniform speed along a circular path. The centripetal force is directed at right angles to the motion and also along the radius towards the centre of the circular path. The mathematical description was derived in 1659 by the Dutch physicist Christiaan Huygens. Formula From the kinematics of curved motion it is known ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Revolutions Per Minute
Revolutions per minute (abbreviated rpm, RPM, rev/min, r/min, or r⋅min−1) is a unit of rotational speed (or rotational frequency) for rotating machines. One revolution per minute is equivalent to hertz. Standards ISO 80000-3:2019 defines a physical quantity called ''rotation'' (or ''number of revolutions''), dimensionless, whose instantaneous rate of change is called ''rotational frequency'' (or ''rate of rotation''), with units of reciprocal seconds (s−1). A related but distinct quantity for describing rotation is ''angular frequency'' (or ''angular speed'', the magnitude of angular velocity), for which the SI unit is the radian per second (rad/s). Although they have the same dimensions (reciprocal time) and base unit (s−1), the hertz (Hz) and radians per second (rad/s) are special names used to express two different but proportional ISQ quantities: frequency and angular frequency, respectively. The conversions between a frequency and an angular frequency ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dizziness
Dizziness is an imprecise term that can refer to a sense of disorientation in space, vertigo, or lightheadedness. It can also refer to Balance disorder, disequilibrium or a non-specific feeling, such as giddiness or foolishness. Dizziness is a common medical complaint, affecting 20–30% of persons. Dizziness is broken down into four main subtypes: vertigo (~25–50%), equilibrioception#Dysfunction, disequilibrium (less than ~15%), presyncope (less than ~15%), and nonspecific dizziness (~10%). * Vertigo is the sensation of spinning or having one's surroundings spin about them. Many people find vertigo very disturbing and often report associated nausea and vomiting. * Presyncope describes lightheadedness or feeling faint; the name relates to Syncope (medicine), syncope, which is actually fainting. * equilibrioception#Dysfunction, Disequilibrium is the sensation of being off balance and is most often characterized by frequent falls in a specific direction. This condition is not of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Semicircular Canals
The semicircular canals are three semicircular interconnected tubes located in the innermost part of each ear, the inner ear. The three canals are the lateral, anterior and posterior semicircular canals. They are the part of the bony labyrinth, a periosteum-lined cavity on the petrous part of the temporal bone filled with perilymph. Each semicircular canal contains its respective semicircular duct, i.e. the lateral, anterior and posterior semicircular ducts, which provide the sensation of angular acceleration and are part of the membranous labyrinth—therefore filled with endolymph. Structure The semicircular canals are a component of the bony labyrinth that are at right angles from each other and contain their respective semicircular duct. At one end of each of the semicircular ducts is a dilated sac called a membranous ampulla, which is more than twice the diameter of the ducts. Each ampulla contains an ampullary crest, the crista ampullaris which consists of a t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronaut
An astronaut (from the Ancient Greek (), meaning 'star', and (), meaning 'sailor') is a person trained, equipped, and deployed by a List of human spaceflight programs, human spaceflight program to serve as a commander or crew member of a spacecraft. Although generally reserved for professional space travelers, the term is sometimes applied to anyone who travels into space, including scientists, politicians, journalists, and space tourists. "Astronaut" technically applies to all human space travelers regardless of nationality. However, astronauts fielded by Russia or the Soviet Union are typically known instead as cosmonauts (from the Russian "kosmos" (космос), meaning "space", also borrowed from Greek ). Comparatively recent developments in crewed spaceflight made by China have led to the rise of the term taikonaut (from the Standard Chinese, Mandarin "tàikōng" (), meaning "space"), although its use is somewhat informal and its origin is unclear. In China, the People' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Coriolis Effect
In physics, the Coriolis force is a pseudo force that acts on objects in motion within a frame of reference that rotates with respect to an inertial frame. In a reference frame with clockwise rotation, the force acts to the left of the motion of the object. In one with anticlockwise (or counterclockwise) rotation, the force acts to the right. Deflection of an object due to the Coriolis force is called the Coriolis effect. Though recognized previously by others, the mathematical expression for the Coriolis force appeared in an 1835 paper by French scientist Gaspard-Gustave de Coriolis, in connection with the theory of water wheels. Early in the 20th century, the term ''Coriolis force'' began to be used in connection with meteorology. Newton's laws of motion describe the motion of an object in an inertial (non-accelerating) frame of reference. When Newton's laws are transformed to a rotating frame of reference, the Coriolis and centrifugal accelerations appear. When applied ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Centrifuge
A centrifuge is a device that uses centrifugal force to subject a specimen to a specified constant force - for example, to separate various components of a fluid. This is achieved by spinning the fluid at high speed within a container, thereby separating fluids of different densities (e.g. cream from milk) or liquids from solids. It works by causing denser substances and particles to move outward in the radial direction. At the same time, objects that are less dense are displaced and moved to the centre. In a laboratory centrifuge that uses sample tubes, the radial acceleration causes denser particles to settle to the bottom of the tube, while low-density substances rise to the top. A centrifuge can be a very effective filter that separates contaminants from the main body of fluid. Industrial scale centrifuges are commonly used in manufacturing and waste processing to sediment suspended solids, or to separate immiscible liquids. An example is the cream separator found in da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bion 4
Kosmos 936 or Bion 4 (''Бион 4'', ''Космос 936'') was a Bion satellite. The mission involved nine countries in a series of biomedical research experiments. The experiments were primarily follow-ups to the Bion 3 (Kosmos 782) flight. Scientists from the Bulgaria, Czechoslovakia, East Germany, France, Hungary, Poland, Romania, the United States and the Soviet Union conducted experiments in physics and biology on the mission. Spacecraft The spacecraft was based on the Zenit reconnaissance satellite and launches began in 1973 with primary emphasis on the problems of radiation effects on human beings. Launches in the program included Kosmos 110, 605, 670, 782, plus Nauka modules flown on Zenit-2M reconnaissance satellites. 90 kg of equipment could be contained in the external Nauka module. Launch Kosmos 936 was launched on 3 August 1977, at 14:01:00 UTC by a Soyuz-U launch vehicle from Plesetsk Cosmodrome. The mission ended after 19.5 days. Mission The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bion 3
Kosmos 782 or Bion 3 (Бион 3, Космос 782) was a Bion satellite. It carried 14 experiments prepared by seven countries in all, with participation from scientists in France, Czechoslovakia, Hungary, Poland, Romania, United States and the Soviet Union. Launch and return Launched from Plesetsk Cosmodrome on 25 November 1975, at 14:00:00 UTC. The biosatellite was recovered near Amankaragaj, in Kazakhstan, Soviet Union, on 15 December 1975 after 19.5 days. Mission It included a centrifuge with revolving and fixed sections in which identical groups of animals, plants, and cells could be compared. The subject animals included white rats and tortoises. The effects of aging on fruit fly livers and plant tissues with grafted cancerous growths were also studied. More than 20 different species were flown on the mission, including 25 unrestrained male Wistar rats, fruit flies (''Drosophila melanogaster''), carrot tissues, and 1,000 embryos of the fish ''Fundulus heteroclitus'' ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Little G
The gravity of Earth, denoted by , is the net acceleration that is imparted to objects due to the combined effect of gravitation (from mass distribution within Earth) and the centrifugal force (from the Earth's rotation). It is a vector quantity, whose direction coincides with a plumb bob and strength or magnitude is given by the norm g=\, \mathit\, . In SI units, this acceleration is expressed in metres per second squared (in symbols, m/ s2 or m·s−2) or equivalently in newtons per kilogram (N/kg or N·kg−1). Near Earth's surface, the acceleration due to gravity, accurate to 2 significant figures, is . This means that, ignoring the effects of air resistance, the speed of an object falling freely will increase by about every second. The precise strength of Earth's gravity varies with location. The agreed-upon value for is by definition. This quantity is denoted variously as , (though this sometimes means the normal gravity at the equator, ), , or simply (which is als ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
