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99942 Apophis

Index 99942 Apophis

99942 Apophis (previously known by its provisional designation) is a near-Earth asteroid that caused a brief period of concern in December 2004 because initial observations indicated a probability of up to 2.7% that it would hit Earth on April 13, 2029. [1]

143 relations: Accelerometer, Adaptive optics, Africa, Airbus, Anatoly Perminov, Ancient Egypt, Angular diameter, Apep, Apocalyptic and post-apocalyptic fiction, Apollo asteroid, Apollo program, Apparent magnitude, Arecibo Observatory, ArXiv, Asia, Asteroid impact avoidance, Astrium, Astronomical unit, Aten asteroid, Atlantic Ocean, B612 Foundation, Bild, Binoculars, Bok Telescope, California, Cambridge University Press, Canadian Broadcasting Corporation, Chicxulub crater, Colombia, Common Dreads, Communications satellite, Costa Rica, David J. Tholen, Dead Again (Type O Negative album), Degree (angle), Don Quijote (spacecraft), Duat, Earth, Earth radius, Elecnor Deimos, Enter Shikari, Europe, European Space Agency, Fabrizio Bernardi, Geosynchronous orbit, Geosynchronous satellite, Goa'uld characters in Stargate, Goldstone Deep Space Communications Complex, Gravitational keyhole, Gravity tractor, ..., Greek language, Herschel Space Observatory, Hong Kong Polytechnic University, Hong Kong University of Science and Technology, Id Software, Impact crater, Impact event, Impact winter, Institute for Astronomy, Intercontinental ballistic missile, Julian day, Julian year (astronomy), Kelvin, Kinetic energy, Kitt Peak National Observatory, Krakatoa, Laser rangefinder, Madrid, Magnetometer, Makeyev Rocket Design Bureau, Massachusetts Institute of Technology School of Science, Meteor Crater, Mexico, Minor Planet Center, Minotaur (rocket family), Minute and second of arc, Monash University, Moon, Multispectral image, Naked eye, NASA, NASA Infrared Telescope Facility, Near-Earth object, Near-infrared spectroscopy, NEODyS, Nicaragua, Nico Marquardt, Non-inclined orbit, Nuclear weapon, Observation arc, Open University, Optical resolution, Orbital resonance, Pacific Ocean, Palermo Technical Impact Hazard Scale, Perturbation (astronomy), Planet, Popular Mechanics, Potentially hazardous object, Precovery, Principal investigator, Provisional designation in astronomy, Ra, Radar, Radar astronomy, Rage (video game), Retrograde and prograde motion, Roscosmos, Roy A. Tucker, Royal Observatory of Belgium, Russia, Rusty Schweickart, Second, Sedimentary rock, Semi-major and semi-minor axes, Sentry (monitoring system), Set (deity), Sky & Telescope, SpaceWorks Enterprises, Spain, Stargate SG-1, Sun, Telespazio, The Aerospace Corporation, The Planetary Society, Thermonuclear weapon, TNT equivalent, Torino scale, Transponder, Tsar Bomba, Tsinghua University, Tsunami, Tunguska event, Type O Negative, University of Michigan, University of Pisa, University of Stuttgart, University of Valladolid, Venezuela, Video game, Yarkovsky effect, (175706) 1996 FG3, 1,000,000,000. Expand index (93 more) »


An accelerometer is a device that measures proper acceleration.

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Adaptive optics

Adaptive optics (AO) is a technology used to improve the performance of optical systems by reducing the effect of incoming wavefront distortions by deforming a mirror in order to compensate for the distortion.

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Africa is the world's second largest and second most-populous continent (behind Asia in both categories).

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Airbus SE is a European corporation, registered in the Netherlands and trading shares in France, Germany and Spain.

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Anatoly Perminov

Anatoly Nikolayevich Perminov (Анатолий Николаевич Перминов; born 16 June 1945 in the Kirov Oblast, Soviet Union) is a Russian rocket scientist and a mechanical engineer.

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Ancient Egypt

Ancient Egypt was a civilization of ancient Northeastern Africa, concentrated along the lower reaches of the Nile River - geographically Lower Egypt and Upper Egypt, in the place that is now occupied by the countries of Egypt and Sudan.

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Angular diameter

The angular diameter, angular size, apparent diameter, or apparent size is an angular measurement describing how large a sphere or circle appears from a given point of view.

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Apep (or; also spelled Apepi or Aapep) or Apophis (Ἄποφις) was the ancient Egyptian deity who embodied chaos (ı͗zft in Egyptian) and was thus the opponent of light and Ma'at (order/truth).

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Apocalyptic and post-apocalyptic fiction

Apocalyptic and post-apocalyptic fiction is a subgenre of science fiction, science fantasy or horror in which the Earth's technological civilization is collapsing or has collapsed.

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Apollo asteroid

The Apollo asteroids are a group of near-Earth asteroids named after 1862 Apollo, discovered by German astronomer Karl Reinmuth in the 1930s.

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Apollo program

The Apollo program, also known as Project Apollo, was the third United States human spaceflight program carried out by the National Aeronautics and Space Administration (NASA), which accomplished landing the first humans on the Moon from 1969 to 1972.

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Apparent magnitude

The apparent magnitude of a celestial object is a number that is a measure of its brightness as seen by an observer on Earth.

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Arecibo Observatory

The Arecibo Observatory is a radio telescope in the municipality of Arecibo, Puerto Rico.

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arXiv (pronounced "archive") is a repository of electronic preprints (known as e-prints) approved for publication after moderation, that consists of scientific papers in the fields of mathematics, physics, astronomy, computer science, quantitative biology, statistics, and quantitative finance, which can be accessed online.

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Asia is Earth's largest and most populous continent, located primarily in the Eastern and Northern Hemispheres.

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Asteroid impact avoidance

Asteroid impact avoidance comprises a number of methods by which near-Earth objects (NEO) could be diverted, preventing destructive impact events.

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Astrium was an aerospace manufacturer subsidiary of the European Aeronautic Defence and Space Company (EADS) that provided civil and military space systems and services from 2006 to 2013.

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Astronomical unit

The astronomical unit (symbol: au, ua, or AU) is a unit of length, roughly the distance from Earth to the Sun.

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Aten asteroid

The Aten asteroids are a dynamical group of asteroids whose orbits bring them into proximity with Earth.

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Atlantic Ocean

The Atlantic Ocean is the second largest of the world's oceans with a total area of about.

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B612 Foundation

The B612 Foundation is a private nonprofit foundation headquartered in Mill Valley, California, United States, dedicated to planetary defense against asteroids and other near-Earth object (NEO) impacts.

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The Bild newspaper (or Bild-Zeitung, literally Picture) is a German tabloid published by Axel Springer AG.

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Binoculars or field glasses are two telescopes mounted side-by-side and aligned to point in the same direction, allowing the viewer to use both eyes (binocular vision) when viewing distant objects.

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Bok Telescope

The Bok Telescope (also known as the 90-inch) is the largest telescope operated solely by Steward Observatory.

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California is a state in the Pacific Region of the United States.

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Cambridge University Press

Cambridge University Press (CUP) is the publishing business of the University of Cambridge.

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Canadian Broadcasting Corporation

The Canadian Broadcasting Corporation (Société Radio-Canada), branded as CBC/Radio-Canada, is a Canadian federal Crown corporation that serves as the national public broadcaster for both radio and television.

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Chicxulub crater

The Chicxulub crater is an impact crater buried underneath the Yucatán Peninsula in Mexico.

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Colombia, officially the Republic of Colombia, is a sovereign state largely situated in the northwest of South America, with territories in Central America.

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Common Dreads

Common Dreads is the second studio album by English rock band Enter Shikari released on 15 June 2009 and 16 June in the US.

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Communications satellite

A communications satellite is an artificial satellite that relays and amplifies radio telecommunications signals via a transponder; it creates a communication channel between a source transmitter and a receiver at different locations on Earth.

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Costa Rica

Costa Rica ("Rich Coast"), officially the Republic of Costa Rica (República de Costa Rica), is a country in Central America, bordered by Nicaragua to the north, Panama to the southeast, the Pacific Ocean to the west, the Caribbean Sea to the east, and Ecuador to the south of Cocos Island.

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David J. Tholen

David James Tholen (born 1955) is an American astronomer at the Institute for Astronomy of the University of Hawaii.

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Dead Again (Type O Negative album)

Dead Again is the seventh and final studio album by Type O Negative, released before the death of frontman Peter Steele.

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Degree (angle)

A degree (in full, a degree of arc, arc degree, or arcdegree), usually denoted by ° (the degree symbol), is a measurement of a plane angle, defined so that a full rotation is 360 degrees.

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Don Quijote (spacecraft)

Don Quijote is a past space probe concept that has been studied by the European Space Agency, and which would investigate the effects of crashing a spacecraft into an asteroid.

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Duat (pronounced "do-aht") (also Tuat and Tuaut or Akert, Amenthes, Amenti, or Neter-khertet) was the realm of the dead in ancient Egyptian mythology.

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Earth is the third planet from the Sun and the only astronomical object known to harbor life.

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Earth radius

Earth radius is the approximate distance from Earth's center to its surface, about.

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Elecnor Deimos

Elecnor Deimos is Elecnor's technological arm.

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Enter Shikari

Enter Shikari are a British alternative rock band formed in St Albans, Hertfordshire, England in 1999 under the name Hybryd by bassist Chris Batten, lead vocalist and keyboardist Roughton "Rou" Reynolds, and drummer Rob Rolfe.

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Europe is a continent located entirely in the Northern Hemisphere and mostly in the Eastern Hemisphere.

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European Space Agency

The European Space Agency (ESA; Agence spatiale européenne, ASE; Europäische Weltraumorganisation) is an intergovernmental organisation of 22 member states dedicated to the exploration of space.

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Fabrizio Bernardi

Fabrizio Bernardi (born 1972) is an Italian astronomer and discoverer of minor planets and comets, best known for the co-discovery of the near-Earth and potentially hazardous asteroid 99942 Apophis.

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Geosynchronous orbit

A geosynchronous orbit (sometimes abbreviated GSO) is an orbit around Earth of a satellite with an orbital period that matches Earth's rotation on its axis, which takes one sidereal day (23 hours, 56 minutes, and 4 seconds).

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Geosynchronous satellite

A geosynchronous satellite is a satellite in geosynchronous orbit, with an orbital period the same as the Earth's rotation period.

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Goa'uld characters in Stargate

This is a list of the Goa'uld characters that appear in Stargate, Stargate SG-1, and Stargate Atlantis.

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Goldstone Deep Space Communications Complex

The Goldstone Deep Space Communications Complex (GDSCC), commonly called the Goldstone Observatory, is located in the Mojave Desert near Barstow in the U.S. state of California.

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Gravitational keyhole

A gravitational keyhole is a tiny region of space where a planet's gravity would alter the orbit of a passing asteroid such that the asteroid would collide with that planet on a given future orbital pass.

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Gravity tractor

A gravity tractor is a theoretical spacecraft that would deflect another object in space, typically a potentially hazardous asteroid that might impact Earth, without physically contacting it, using only its gravitational field to transmit the required impulse.

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Greek language

Greek (Modern Greek: ελληνικά, elliniká, "Greek", ελληνική γλώσσα, ellinikí glóssa, "Greek language") is an independent branch of the Indo-European family of languages, native to Greece and other parts of the Eastern Mediterranean and the Black Sea.

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Herschel Space Observatory

The Herschel Space Observatory was a space observatory built and operated by the European Space Agency (ESA).

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Hong Kong Polytechnic University

The Hong Kong Polytechnic University (PolyU) is a public university located in Hung Hom, Hong Kong.

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Hong Kong University of Science and Technology

The Hong Kong University of Science and Technology (HKUST) is a public research university in Clear Water Bay, Hong Kong.

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Id Software

id Software LLC (see Company name) is an American video game developer headquartered in Dallas, Texas.

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Impact crater

An impact crater is an approximately circular depression in the surface of a planet, moon, or other solid body in the Solar System or elsewhere, formed by the hypervelocity impact of a smaller body.

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Impact event

An impact event is a collision between astronomical objects causing measurable effects.

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Impact winter

An impact winter is a hypothesized period of prolonged cold weather due to the impact of a large asteroid or comet on the Earth's surface.

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Institute for Astronomy

The Institute for Astronomy (IfA) is a research unit within the University of Hawaii system, led by Robert McLaren as Acting Director.

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Intercontinental ballistic missile

An intercontinental ballistic missile (ICBM) is a guided ballistic missile with a minimum range of primarily designed for nuclear weapons delivery (delivering one or more thermonuclear warheads).

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Julian day

Julian day is the continuous count of days since the beginning of the Julian Period and is used primarily by astronomers.

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Julian year (astronomy)

In astronomy, a Julian year (symbol: a) is a unit of measurement of time defined as exactly 365.25 days of SI seconds each.

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The Kelvin scale is an absolute thermodynamic temperature scale using as its null point absolute zero, the temperature at which all thermal motion ceases in the classical description of thermodynamics.

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Kinetic energy

In physics, the kinetic energy of an object is the energy that it possesses due to its motion.

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Kitt Peak National Observatory

The Kitt Peak National Observatory (KPNO) is a United States astronomical observatory located on Kitt Peak of the Quinlan Mountains in the Arizona-Sonoran Desert on the Tohono O'odham Nation, west-southwest of Tucson, Arizona.

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Krakatoa, or Krakatau (Krakatau), is a volcanic island situated in the Sunda Strait between the islands of Java and Sumatra in the Indonesian province of Lampung.

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Laser rangefinder

A laser rangefinder is a rangefinder that uses a laser beam to determine the distance to an object.

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Madrid is the capital of Spain and the largest municipality in both the Community of Madrid and Spain as a whole.

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A magnetometer is an instrument that measures magnetism—either the magnetization of a magnetic material like a ferromagnet, or the direction, strength, or relative change of a magnetic field at a particular location.

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Makeyev Rocket Design Bureau

The Makeyev Design Bureau (ГРЦ Макеева, also known as Makeyev OKB) is a Russian missile design company located in Miass, Russia.

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Massachusetts Institute of Technology School of Science

The MIT School of Science is one of the five schools of the Massachusetts Institute of Technology, located in Cambridge, Massachusetts, United States.

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Meteor Crater

Meteor Crater is a meteorite impact crater approximately east of Flagstaff and west of Winslow in the northern Arizona desert of the United States.

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Mexico (México; Mēxihco), officially called the United Mexican States (Estados Unidos Mexicanos) is a federal republic in the southern portion of North America.

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Minor Planet Center

The Minor Planet Center (MPC) is the official worldwide organization in charge of collecting observational data for minor planets (such as asteroids and comets), calculating their orbits and publishing this information via the Minor Planet Circulars.

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Minotaur (rocket family)

The Minotaur is a family of American solid fuel rockets derived from converted Minuteman and Peacekeeper intercontinental ballistic missiles.

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Minute and second of arc

A minute of arc, arcminute (arcmin), arc minute, or minute arc is a unit of angular measurement equal to of one degree.

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Monash University

Monash University is a public research university based in Melbourne, Australia.

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The Moon is an astronomical body that orbits planet Earth and is Earth's only permanent natural satellite.

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Multispectral image

A multispectral image is one that captures image data within specific wavelength ranges across the electromagnetic spectrum.

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Naked eye

Naked eye, also called bare eye or unaided eye, is the practice of engaging in visual perception unaided by a magnifying or light-collecting optical instrument, such as a telescope or microscope.

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The National Aeronautics and Space Administration (NASA) is an independent agency of the executive branch of the United States federal government responsible for the civilian space program, as well as aeronautics and aerospace research.

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NASA Infrared Telescope Facility

The NASA Infrared Telescope Facility (NASA IRTF) is a telescope optimized for use in infrared astronomy and located at the Mauna Kea Observatory in Hawaii.

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Near-Earth object

A near-Earth object (NEO) is any small Solar System body whose orbit can bring it into proximity with Earth.

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Near-infrared spectroscopy

Near-infrared spectroscopy (NIRS) is a spectroscopic method that uses the near-infrared region of the electromagnetic spectrum (from 780 nm to 2500 nm).

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NEODyS (Near Earth Objects Dynamic Site) is an Italian and Spanish service that provides information on Near Earth Objects with a Web-based interface.

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Nicaragua, officially the Republic of Nicaragua, is the largest country in the Central American isthmus, bordered by Honduras to the north, the Caribbean to the east, Costa Rica to the south, and the Pacific Ocean to the west.

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Nico Marquardt

Nico Marquardt (born May 24, 1994 in Potsdam) is a German politician, non-executive director and consultant.

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Non-inclined orbit

A non-inclined orbit is an orbit coplanar with a plane of reference.

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Nuclear weapon

A nuclear weapon is an explosive device that derives its destructive force from nuclear reactions, either fission (fission bomb) or from a combination of fission and fusion reactions (thermonuclear bomb).

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Observation arc

In observational astronomy, an observation arc (or arc length) is the time period between the first and most recent (last) observation, tracing the body's path.

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Open University

The Open University (OU) is a public distance learning and research university, and one of the biggest universities in the UK for undergraduate education.

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Optical resolution

Optical resolution describes the ability of an imaging system to resolve detail in the object that is being imaged.

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Orbital resonance

In celestial mechanics, an orbital resonance occurs when orbiting bodies exert a regular, periodic gravitational influence on each other, usually because their orbital periods are related by a ratio of small integers.

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Pacific Ocean

The Pacific Ocean is the largest and deepest of Earth's oceanic divisions.

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Palermo Technical Impact Hazard Scale

The Palermo Technical Impact Hazard Scale is a logarithmic scale used by astronomers to rate the potential hazard of impact of a near-earth object (NEO).

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Perturbation (astronomy)

In astronomy, perturbation is the complex motion of a massive body subject to forces other than the gravitational attraction of a single other massive body.

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A planet is an astronomical body orbiting a star or stellar remnant that is massive enough to be rounded by its own gravity, is not massive enough to cause thermonuclear fusion, and has cleared its neighbouring region of planetesimals.

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Popular Mechanics

Popular Mechanics is a classic magazine of popular science and technology.

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Potentially hazardous object

A potentially hazardous object (PHO) is a near-Earth object – either an asteroid or a comet – with an orbit that can make exceptionally close approaches to the Earth and large enough to cause significant regional damage in the event of impact.

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In astronomy, precovery (short for pre-discovery recovery) is the process of finding the image of an object in old archived images or photographic plates for the purpose of calculating a more accurate orbit.

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Principal investigator

A principal investigator (PI) is the holder of an independent grant administered by a university and the lead researcher for the grant project, usually in the sciences, such as a laboratory study or a clinical trial.

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Provisional designation in astronomy

Provisional designation in astronomy is the naming convention applied to astronomical objects immediately following their discovery.

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Ra (rꜥ or rˤ; also transliterated rˤw; cuneiform: ri-a or ri-ia) or Re (ⲣⲏ, Rē) is the ancient Egyptian sun god.

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Radar is an object-detection system that uses radio waves to determine the range, angle, or velocity of objects.

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Radar astronomy

Radar astronomy is a technique of observing nearby astronomical objects by reflecting microwaves off target objects and analyzing the reflections.

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Rage (video game)

Rage (stylized as RAGE) is a first-person shooter video game developed by id Software, released in November 2010 for iOS and later October 2011 for Microsoft Windows, the PlayStation 3, and the Xbox 360.

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Retrograde and prograde motion

Retrograde motion in astronomy is, in general, orbital or rotational motion of an object in the direction opposite the rotation of its primary, that is the central object (right figure).

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The Roscosmos State Corporation for Space Activities (Государственная корпорация по космической деятельности «Роскосмос»), commonly known as Roscosmos (Роскосмос), is a state corporation responsible for the space flight and cosmonautics program for the Russian Federation.

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Roy A. Tucker

Roy A. Tucker (born 1951 in Jackson, Mississippi) is an American astronomer best known for the co-discovery of near-Earth asteroid 99942 Apophis (formerly known as) along with David J. Tholen and Fabrizio Bernardi of the University of Hawaii.

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Royal Observatory of Belgium

The Royal Observatory of Belgium (Koninklijke Sterrenwacht van België; Observatoire Royal de Belgique), has been situated in Uccle (Ukkel in Dutch) since 1890.

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Russia (rɐˈsʲijə), officially the Russian Federation (p), is a country in Eurasia. At, Russia is the largest country in the world by area, covering more than one-eighth of the Earth's inhabited land area, and the ninth most populous, with over 144 million people as of December 2017, excluding Crimea. About 77% of the population live in the western, European part of the country. Russia's capital Moscow is one of the largest cities in the world; other major cities include Saint Petersburg, Novosibirsk, Yekaterinburg and Nizhny Novgorod. Extending across the entirety of Northern Asia and much of Eastern Europe, Russia spans eleven time zones and incorporates a wide range of environments and landforms. From northwest to southeast, Russia shares land borders with Norway, Finland, Estonia, Latvia, Lithuania and Poland (both with Kaliningrad Oblast), Belarus, Ukraine, Georgia, Azerbaijan, Kazakhstan, China, Mongolia and North Korea. It shares maritime borders with Japan by the Sea of Okhotsk and the U.S. state of Alaska across the Bering Strait. The East Slavs emerged as a recognizable group in Europe between the 3rd and 8th centuries AD. Founded and ruled by a Varangian warrior elite and their descendants, the medieval state of Rus arose in the 9th century. In 988 it adopted Orthodox Christianity from the Byzantine Empire, beginning the synthesis of Byzantine and Slavic cultures that defined Russian culture for the next millennium. Rus' ultimately disintegrated into a number of smaller states; most of the Rus' lands were overrun by the Mongol invasion and became tributaries of the nomadic Golden Horde in the 13th century. The Grand Duchy of Moscow gradually reunified the surrounding Russian principalities, achieved independence from the Golden Horde. By the 18th century, the nation had greatly expanded through conquest, annexation, and exploration to become the Russian Empire, which was the third largest empire in history, stretching from Poland on the west to Alaska on the east. Following the Russian Revolution, the Russian Soviet Federative Socialist Republic became the largest and leading constituent of the Union of Soviet Socialist Republics, the world's first constitutionally socialist state. The Soviet Union played a decisive role in the Allied victory in World War II, and emerged as a recognized superpower and rival to the United States during the Cold War. The Soviet era saw some of the most significant technological achievements of the 20th century, including the world's first human-made satellite and the launching of the first humans in space. By the end of 1990, the Soviet Union had the world's second largest economy, largest standing military in the world and the largest stockpile of weapons of mass destruction. Following the dissolution of the Soviet Union in 1991, twelve independent republics emerged from the USSR: Russia, Ukraine, Belarus, Kazakhstan, Uzbekistan, Armenia, Azerbaijan, Georgia, Kyrgyzstan, Moldova, Tajikistan, Turkmenistan and the Baltic states regained independence: Estonia, Latvia, Lithuania; the Russian SFSR reconstituted itself as the Russian Federation and is recognized as the continuing legal personality and a successor of the Soviet Union. It is governed as a federal semi-presidential republic. The Russian economy ranks as the twelfth largest by nominal GDP and sixth largest by purchasing power parity in 2015. Russia's extensive mineral and energy resources are the largest such reserves in the world, making it one of the leading producers of oil and natural gas globally. The country is one of the five recognized nuclear weapons states and possesses the largest stockpile of weapons of mass destruction. Russia is a great power as well as a regional power and has been characterised as a potential superpower. It is a permanent member of the United Nations Security Council and an active global partner of ASEAN, as well as a member of the G20, the Shanghai Cooperation Organisation (SCO), the Council of Europe, the Asia-Pacific Economic Cooperation (APEC), the Organization for Security and Co-operation in Europe (OSCE), and the World Trade Organization (WTO), as well as being the leading member of the Commonwealth of Independent States (CIS), the Collective Security Treaty Organization (CSTO) and one of the five members of the Eurasian Economic Union (EEU), along with Armenia, Belarus, Kazakhstan and Kyrgyzstan.

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Rusty Schweickart

Russell Louis "Rusty" Schweickart (also Schweikart; born October 25, 1935) is an American aeronautical engineer, and a former NASA astronaut, research scientist, U.S. Air Force fighter pilot, as well as a former business executive and government executive.

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The second is the SI base unit of time, commonly understood and historically defined as 1/86,400 of a day – this factor derived from the division of the day first into 24 hours, then to 60 minutes and finally to 60 seconds each.

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Sedimentary rock

Sedimentary rocks are types of rock that are formed by the deposition and subsequent cementation of that material at the Earth's surface and within bodies of water.

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Semi-major and semi-minor axes

In geometry, the major axis of an ellipse is its longest diameter: a line segment that runs through the center and both foci, with ends at the widest points of the perimeter.

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Sentry (monitoring system)

Since 2002, Sentry has been a highly automated collision monitoring system that continually scans the most current asteroid catalog for possibilities of future impact with Earth over the next 100+ years.

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Set (deity)

Set or Seth (Egyptian: stẖ; also transliterated Setesh, Sutekh, Setekh, or Suty) is a god of the desert, storms, disorder, violence, and foreigners in ancient Egyptian religion.

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Sky & Telescope

Sky & Telescope (S&T) is a monthly American magazine covering all aspects of amateur astronomy, including the following.

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SpaceWorks Enterprises

SpaceWorks Enterprises, Inc. (SEI) is an aerospace engineering company based in Atlanta, Georgia, United States that specializes in the design and assessment of advanced space concepts for both government and commercial customers.

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Spain (España), officially the Kingdom of Spain (Reino de España), is a sovereign state mostly located on the Iberian Peninsula in Europe.

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Stargate SG-1

Stargate SG-1 (often abbreviated as SG-1) is a Canadian-American military science fiction adventure television series and part of Metro-Goldwyn-Mayer's ''Stargate'' franchise.

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The Sun is the star at the center of the Solar System.

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Telespazio Spa is a European spaceflight services company.

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The Aerospace Corporation

The Aerospace Corporation is a California nonprofit corporation that operates a federally funded research and development center (FFRDC) headquartered in El Segundo, California.

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The Planetary Society

The Planetary Society is an American internationally active, non-governmental, nonprofit foundation.

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Thermonuclear weapon

A thermonuclear weapon is a second-generation nuclear weapon design using a secondary nuclear fusion stage consisting of implosion tamper, fusion fuel, and spark plug which is bombarded by the energy released by the detonation of a primary fission bomb within, compressing the fuel material (tritium, deuterium or lithium deuteride) and causing a fusion reaction.

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TNT equivalent

TNT equivalent is a convention for expressing energy, typically used to describe the energy released in an explosion.

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Torino scale

The Torino Scale is a method for categorizing the impact hazard associated with near-Earth objects (NEOs) such as asteroids and comets.

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In telecommunication, a transponder can be one of two types of devices.

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Tsar Bomba

Tsar Bomba was the Western nickname for the Soviet RDS-220 hydrogen bomb (code name Ivan or Vanya), the most powerful nuclear weapon ever created.

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Tsinghua University

Tsinghua University (abbreviated THU;; also romanized as Qinghua) is a major research university in Beijing, China and a member of the elite C9 League of Chinese universities.

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A tsunami (from 津波, "harbour wave"; English pronunciation) or tidal wave, also known as a seismic sea wave, is a series of waves in a water body caused by the displacement of a large volume of water, generally in an ocean or a large lake.

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Tunguska event

The Tunguska event was a large explosion that occurred near the Stony Tunguska River in Yeniseysk Governorate (now Krasnoyarsk Krai), Russia, on the morning of 30 June 1908 (NS).

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Type O Negative

Type O Negative was an American gothic metal band formed in Brooklyn, New York in 1989, by Peter Steele (lead vocals, bass), Kenny Hickey (guitar, backing vocals), Josh Silver (keyboards, backing vocals), and Sal Abruscato (drums, percussions), who was later replaced by Johnny Kelly.

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University of Michigan

The University of Michigan (UM, U-M, U of M, or UMich), often simply referred to as Michigan, is a public research university in Ann Arbor, Michigan.

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University of Pisa

The University of Pisa (Università di Pisa, UniPi) is an Italian public research university located in Pisa, Italy.

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University of Stuttgart

The University of Stuttgart (Universität Stuttgart) is a university located in Stuttgart, Germany.

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University of Valladolid

The University of Valladolid is a public university in the city of Valladolid, province of Valladolid, in the autonomous region of Castile and Leon, Spain.

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Venezuela, officially denominated Bolivarian Republic of Venezuela (República Bolivariana de Venezuela),Previously, the official name was Estado de Venezuela (1830–1856), República de Venezuela (1856–1864), Estados Unidos de Venezuela (1864–1953), and again República de Venezuela (1953–1999).

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Video game

A video game is an electronic game that involves interaction with a user interface to generate visual feedback on a video device such as a TV screen or computer monitor.

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Yarkovsky effect

The Yarkovsky effect is a force acting on a rotating body in space caused by the anisotropic emission of thermal photons, which carry momentum.

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(175706) 1996 FG3

is a rare-type carbonaceous binary asteroid, classified as near-Earth object and potentially hazardous asteroid of the Apollo group, approximately 1.7 kilometers in diameter.

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1,000,000,000 (one billion, short scale; one thousand million or milliard, yard, long scale) is the natural number following 999,999,999 and preceding 1,000,000,001.

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Redirects here:

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[1] https://en.wikipedia.org/wiki/99942_Apophis

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