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Statite
A statite (a portmanteau of the words ''static'' and ''satellite'') is a hypothetical type of artificial satellite that employs a solar sail to continuously modify its orbit in ways that gravity alone would not allow. Typically, a statite would use the solar sail to "hover" in a location that would not otherwise be available as a stable geosynchronous orbit. Statites have been proposed that would remain in fixed locations high over Earth's poles, using reflected sunlight to counteract the gravity pulling them down. Statites might also employ their sails to change the shape or velocity of more conventional orbits, depending upon the purpose of the particular statite. The concept of the statite was invented independently and at about the same time by Robert L. Forward (who coined the term "statite") and Colin McInnes, who used the term "halo orbit" (not to be confused with the type of halo orbit discovered by Robert Farquhar). Subsequently, the terms "non- Keplerian orbit" and "ar ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geosynchronous Orbit
A geosynchronous orbit (sometimes abbreviated GSO) is an Earth-centered orbit with an orbital period that matches Earth's rotation on its axis, 23 hours, 56 minutes, and 4 seconds (one sidereal day). The synchronization of rotation and orbital period means that, for an observer on Earth's surface, an object in geosynchronous orbit returns to exactly the same position in the sky after a period of one sidereal day. Over the course of a day, the object's position in the sky may remain still or trace out a path, typically in a figure-8 form, whose precise characteristics depend on the orbit's inclination and eccentricity. A circular geosynchronous orbit has a constant altitude of . A special case of geosynchronous orbit is the geostationary orbit (often abbreviated ''GEO''), which is a circular geosynchronous orbit in Earth's equatorial plane with both inclination and eccentricity equal to 0. A satellite in a geostationary orbit remains in the same position in the sky to observers ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Hypothetical Technologies
Hypothetical technologies are technologies that do not exist yet, but that could exist in the future. They are distinct from emerging technologies, which have achieved some developmental success. Emerging technologies as of 2018 include 3-D metal printing and artificial embryos. Many hypothetical technologies have been the subject of science fiction. The criteria for this list are that the technology: # Must not exist yet # Is credibly proposed to exist in the future (e.g. no perpetual motion machines) # If the technology does not have an existing article (i.e. it is "redlinked"), a reference must be provided for it Biology * Acne vaccine * Anti-evolutionary drug * Antiprion drug * Artificial gametes * Artificial gill * Artificial "super" mitochondria * Caries vaccine * De-extinction * Dyson tree * Ethnic bioweapon * Female sperm * Flying syringe * Hair cloning * HIV vaccine * Humanzee * Life extension * Liquid breathing * Male egg * Nanochondrion * Nootropic * Prime ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Halo Orbit
A halo orbit is a periodic, non-planar orbit associated with one of the L1, L2 or L3 Lagrange points in the three-body problem of orbital mechanics. Although a Lagrange point is just a point in empty space, its peculiar characteristic is that it can be orbited by a Lissajous orbit or by a halo orbit. These can be thought of as resulting from an interaction between the gravitational pull of the two planetary bodies and the Coriolis and centrifugal force on a spacecraft. Halo orbits exist in any three-body system, e.g., a Sun–Earth–orbiting satellite system or an Earth–Moon–orbiting satellite system. Continuous "families" of both northern and southern halo orbits exist at each Lagrange point. Because halo orbits tend to be unstable, station-keeping using thrusters may be required to keep a satellite on the orbit. Most satellites in halo orbit serve scientific purposes, for example space telescopes. Definition and history Robert W. Farquhar first used the name " ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Portmanteau
In linguistics, a blend—also known as a blend word, lexical blend, or portmanteau—is a word formed by combining the meanings, and parts of the sounds, of two or more words together.Garner's Modern American Usage p. 644. English examples include '' smog'', coined by blending ''smoke'' and ''fog'', and '''', from ''motor'' ('' motorist'') and ''hotel''. A blend is similar to a [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sunjammer (spacecraft)
''Sunjammer'' (Solar Sail Demonstrator) was a NASA mission intended to demonstrate a solar sail constructed by LGarde, but was canceled before launch. The largest solar sail made as of 2013, ''Sunjammer'' was named after a 1964 Arthur C. Clarke story of the same name, '' Sunjammer'', in which several solar sails compete in a race to the Moon. ''Sunjammer'' was slated to launch in January 2015 as the secondary payload of a SpaceX Falcon 9 launch vehicle, along with the Earth observation satellite DSCOVR. Citing a lack of confidence in its contractor's ability to deliver, the mission was canceled in October 2014. Spacecraft design Constructed of Kapton in order to withstand the extreme temperatures of space, ''Sunjammer'' has a width and height of , giving it a total surface area of over and making it the largest solar sail as of 2013. Despite its huge surface area, ''Sunjammer'' has a thickness of only 5 μm, giving it an extremely low weight of about and allowing it to be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astrodynamics
Orbital mechanics or astrodynamics is the application of ballistics and celestial mechanics to rockets, satellites, and other spacecraft. The motion of these objects is usually calculated from Newton's laws of motion and the Newton's law of universal gravitation, law of universal gravitation. Astrodynamics is a core discipline within space exploration, space-mission design and control. Celestial mechanics treats more broadly the orbital dynamics of systems under the influence of gravity, including both spacecraft and natural astronomical object, astronomical bodies such as star systems, planets, Natural satellite, moons, and comets. Orbital mechanics focuses on spacecraft trajectory, trajectories, including orbital maneuvers, orbital plane (astronomy), orbital plane changes, and interplanetary transfers, and is used by mission planners to predict the results of spacecraft propulsion, propulsive maneuvers. General relativity is a more exact theory than Newton's laws for calculati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Space Sunshade
A space sunshade or sunshield is something that diverts or otherwise reduces some of the Sun's radiation, preventing it from hitting the Earth and thereby reducing its insolation, which results in reduced heating. Light can be diverted by different methods. The concept of the construction of sunshade as a method of climate engineering dates back to the years 1923, 1929, 1957 and 1978 by the physicist Hermann Oberth. Space mirrors in orbit around the Earth with a diameter of 100 to 300 km, as designed by Hermann Oberth, were intended to focus sunlight on individual regions of the Earth’s surface or deflect it into space so that the solar radiation is weakened in a specifically controlled manner for individual regions on the Earth’s surface. First proposed in 1989, another space sunshade concept involves putting a large occulting disc, or technology of equivalent purpose, between the Earth and Sun. A sunshade could potentially be one climate engineering method for mitiga ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Mirror
A solar mirror contains a Coating, substrate with a reflective layer for reflecting the solar energy, and in most cases an interference layer. This may be a Plane mirror, planar mirror or Parabola, parabolic arrays of solar mirrors used to achieve a substantially concentrated reflection factor for solar energy systems. See article "Heliostat" for more information on solar mirrors used for terrestrial energy. Components Glass or metal substrate The substrate is the mechanical layer which holds the mirror in shape. Glass may also be used as a protective layer to protect the other layers from abrasion and corrosion. Although glass is brittle, it is a good material for this purpose, because it is highly transparent (low optical losses), resistant to ultraviolet light (UV), fairly hard (abrasion resistant), chemically inert, and fairly easy to clean. It is composed of a float glass with high optical transmission characteristics in the visible and infrared ranges, and is confi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dyson Bubble
A Dyson sphere is a hypothetical megastructure that encompasses a star and captures a large percentage of its power output. The concept is a thought experiment that attempts to imagine how a spacefaring civilization would meet its energy requirements once those requirements exceed what can be generated from the home planet's resources alone. Because only a tiny fraction of a star's energy emissions reaches the surface of any orbiting planet, building structures encircling a star would enable a civilization to harvest far more energy. The first modern imagining of such a structure was by Olaf Stapledon in his science fiction novel ''Star Maker'' (1937). The concept was later explored by the physicist Freeman Dyson in his 1960 paper "Search for Artificial Stellar Sources of Infrared Radiation". Dyson speculated that such structures would be the logical consequence of the escalating energy needs of a technological civilization and would be a necessity for its long-term survival. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interstellar Object
An interstellar object is an astronomical object in interstellar space that is not gravitationally bound to a star. Applicable objects include asteroids, comets, and rogue planets, but not a star or stellar remnant. This term can also be applied to an object that is on an interstellar trajectory but is temporarily passing close to a star, such as certain asteroids and comets (that is, exoasteroids and exocomets). In the latter case, the object may be called an interstellar interloper. The first interstellar objects discovered were rogue planets, planets ejected from their original stellar system (e.g., OTS 44 or Cha 110913−773444), though they are difficult to distinguish from sub-brown dwarfs, planet-mass objects that formed in interstellar space as stars do. The first interstellar object which was discovered traveling through the Solar System was ʻOumuamua, 1I/ʻOumuamua in 2017. The second was 2I/Borisov in 2019. They both possess significant Hyperbolic trajectory#Semi-m ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Patricia Mulligan
Patricia is a feminine given name of Latin origin. Derived from the Latin word '' patrician'', meaning 'noble', it is the feminine form of the masculine given name Patrick. Another well-known variant is Patrice. According to the US Social Security Administration records, the use of the name for newborns peaked at #3 from 1937 to 1943 in the United States, after which it dropped in popularity, sliding to #745 in 2016.Popularity of a NameSocial Security Administration''ssa.gov'', accessed June 26, 2017 From 1928 to 1967, the name was ranked among the top 11 female names. In Portuguese and Spanish-speaking Latin-American countries, the name Patrícia/Patricia is common as well, pronounced in Portuguese and in Spanish. In Catalan and Portuguese it is written Patrícia, while in Italy, Germany and Austria Patrizia is the form, pronounced in Italian and in German. In Polish, the variant is Patrycja, pronounced . It is also used in Romania, in 2009 being the 43rd most common nam ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Geomagnetic Storm
A geomagnetic storm, also known as a magnetic storm, is a temporary disturbance of the Earth's magnetosphere that is driven by interactions between the magnetosphere and large-scale transient Plasma (physics), plasma and magnetic field structures that originate on or near the Sun. The structures that produce geomagnetic storms include interplanetary coronal mass ejections (CME) and corotating interaction regions (CIR). The former often originate from solar active regions, while the latter originate at the boundary between high- and low-speed streams of solar wind. The frequency of geomagnetic storms increases and decreases with the sunspot cycle. During solar maximum, solar maxima, geomagnetic storms occur more often, with the majority driven by CMEs. When these structures reach Earth, the increase in the solar wind pressure initially compresses the magnetosphere. The solar wind's magnetic field interacts with the Earth's magnetic field and transfers an increased energy into th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
