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Distant Retrograde Orbit
A distant retrograde orbit (DRO), as most commonly conceived, is a spacecraft orbit around a moon>M2>>M3. So DRO is a general three-body problem solution. It's just that most practical near-term uses for the concept at three-body problems in our Solar System where M1 = a planet, and M2 = a moon of that planet, and M3 = a human-made spacecraft. --> that is highly stable because of its interactions with two Lagrange points ( and ) of the planet–moon system. In more general terms, an object of negligible mass can be in a DRO around the smaller body of any two-body system, such as planet–Sun or exoplanet–star. Using the example of a spacecraft in a DRO around a moon, the craft would orbit in the direction opposite to the direction in which the moon orbits the planet. The orbit is "distant" in the sense that it passes above the Lagrange points, rather than being near the moon. If we consider more and more distant orbits, the synodic period (the period between two moments when the ...
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Orbit
In celestial mechanics, an orbit is the curved trajectory of an object such as the trajectory of a planet around a star, or of a natural satellite around a planet, or of an artificial satellite around an object or position in space such as a planet, moon, asteroid, or Lagrange point. Normally, orbit refers to a regularly repeating trajectory, although it may also refer to a non-repeating trajectory. To a close approximation, planets and satellites follow elliptic orbits, with the center of mass being orbited at a focal point of the ellipse, as described by Kepler's laws of planetary motion. For most situations, orbital motion is adequately approximated by Newtonian mechanics, which explains gravity as a force obeying an inverse-square law. However, Albert Einstein's general theory of relativity, which accounts for gravity as due to curvature of spacetime, with orbits following geodesics, provides a more accurate calculation and understanding of the exact mechanics of orbi ...
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The Space Review
''The Space Review'' is a free online publication, published weekly with in-depth articles, essays, commentary and reviews on space exploration and development. It was founded in February 2003 by Jeff Foust, the current editor, publisher and regular writer. Other regular writers include: * John K. Strickland, National Space Society, Board of Directors * Brian Weeden * Dwayne A. Day * Taylor Dinerman * Sam Dinkin * Anthony Young The publication is known for its coverage of space tourism, as well as NASA and the satellite A satellite or artificial satellite is an object intentionally placed into orbit in outer space. Except for passive satellites, most satellites have an electricity generation system for equipment on board, such as solar panels or radioisotope ... launch industry. References External links ''The Space Review'' {{DEFAULTSORT:Space Review Free magazines Magazines established in 2003 Online magazines published in the United States Weekly magazines publis ...
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Free-return Trajectory
In orbital mechanics, a free-return trajectory is a trajectory of a spacecraft traveling away from a primary body (for example, the Earth) where gravity due to a secondary body (for example, the Moon) causes the spacecraft to return to the primary body without propulsion (hence the term ''free''). Many free-return trajectories are designed to intersect the atmosphere; however, periodic versions exist which pass the moon and Earth at constant periapsis, which have been proposed for cyclers. Earth–Moon The first spacecraft to use a free-return trajectory was the Soviet Luna 3 mission in October 1959. It used the Moon's gravity to send it back towards the Earth so that the photographs it had taken of the far side of the Moon could be downloaded by radio. Symmetrical free-return trajectories were studied by Arthur Schwaniger of NASA in 1963 with reference to the Earth–Moon system. He studied cases in which the trajectory at some point crosses at a right angle the line going ...
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Daniel Suarez (author)
Daniel Suarez (born December 21, 1964) is a former American information technology consultant turned author. He initially published under the pseudonym Leinad Zeraus (his name spelled backwards). Career His career as an author began with a pair of techno-thriller novels. The first novel, ''Daemon'', was self-published under his own company, Verdugo Press, in late 2006. It was later picked up by the major publishing house Dutton and re-released on January 8, 2009. His follow-up book '' Freedom™'' was released on January 7, 2010. ''The Wall Street Journal'' has reported that Walter F. Parkes, who produced the 1983 film ''WarGames'', had optioned the film rights to ''Daemon'' with Paramount Pictures in 2009, but the rights likely reverted to Suarez on 8 December 2012. Suarez announced in November 2011 that he was writing his third novel, "which deals with autonomous drones and next-gen, anonymous warfare" (via his Google Plus Account). That novel, '' Kill Decision'', was release ...
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Near-rectilinear Halo Orbit
A near-rectilinear halo orbit (NRHO) is a halo orbit with slightly curved – or nearly straight – sides between close passes with an orbiting body. The 2022 CAPSTONE mission is the first such orbit in cislunar space, and this Moon-centric orbit will serve as a staging area for future lunar missions. The orbit could be used with other bodies in the Solar System and beyond. A halo orbit is a periodic, three-dimensional orbit associated with one of the L1, L2 and L3 Lagrange points. Near-rectilinear means that some segments of the orbit have a greater curvature than those of an elliptical orbit of the same maximum diameter, and other segments have a curvature less than that of an elliptical orbit of the same maximum diameter (taking maximum diameter as that of the smallest circle that contains the whole of the orbit). In the extreme case all segments have zero curvature with four points with infinite curvature (''i.e.'' a polygon). Such a non-elliptical orbit would require at lea ...
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Cislunar Space
Outer space, commonly shortened to space, is the expanse that exists beyond Earth and its atmosphere and between celestial bodies. Outer space is not completely empty—it is a near-perfect vacuum containing a low density of particles, predominantly a plasma of hydrogen and helium, as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays. The baseline temperature of outer space, as set by the background radiation from the Big Bang, is . The plasma between galaxies is thought to account for about half of the baryonic (ordinary) matter in the universe, having a number density of less than one hydrogen atom per cubic metre and a kinetic temperature of millions of kelvins. Local concentrations of matter have condensed into stars and galaxies. Studies indicate that 90% of the mass in most galaxies is in an unknown form, called dark matter, which interacts with other matter through gravitational but not electromagnetic forces. Observations ...
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Lunar Gateway
The Lunar Gateway, or simply Gateway, is the first planned extraterrestrial space station in lunar orbit intended to serve as a solar-powered communication hub, science laboratory, and short-term habitation module for government-agency astronauts, as well as a holding area for rovers and other robots. It is a multinational collaborative project involving four of the International Space Station partner agencies: NASA, European Space Agency (ESA), Japan Aerospace Exploration Agency (JAXA), and Canadian Space Agency (CSA). It is planned to be both the first space station beyond low Earth orbit and the first space station to orbit the Moon. Formerly known as the Deep Space Gateway (DSG), the station was renamed Lunar Orbital Platform-Gateway (LOP-G) in NASA's 2018 proposal for the 2019 United States federal budget. When the budgeting process was complete, US$332 million had been committed by Congress to preliminary studies. The science disciplines to be studied on the Gatew ...
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Jupiter Icy Moons Orbiter
The ''Jupiter Icy Moons Orbiter'' (JIMO) was a proposed NASA spacecraft designed to explore the icy moons of Jupiter. The main target was Europa, where an ocean of liquid water may harbor alien life. Ganymede and Callisto, which are now thought to have liquid, salty oceans beneath their icy surfaces, were also targets of interest for the probe. The JIMO spacecraft JIMO was to have a large number of revolutionary features. Throughout its main voyage to the Jupiter moons, it was to be propelled by an ion propulsion system via either the High Power Electric Propulsion or NEXIS engine, and powered by a small fission reactor. A Brayton power conversion system would convert reactor heat into electricity. Providing a thousand times the electrical output of conventional solar- or radioisotope thermoelectric generator (RTG)-based power systems, the reactor was expected to open up opportunities like flying a full scale ice-penetrating radar system and providing a strong, high-ba ...
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YouTube
YouTube is a global online video platform, online video sharing and social media, social media platform headquartered in San Bruno, California. It was launched on February 14, 2005, by Steve Chen, Chad Hurley, and Jawed Karim. It is owned by Google, and is the List of most visited websites, second most visited website, after Google Search. YouTube has more than 2.5 billion monthly users who collectively watch more than one billion hours of videos each day. , videos were being uploaded at a rate of more than 500 hours of content per minute. In October 2006, YouTube was bought by Google for $1.65 billion. Google's ownership of YouTube expanded the site's business model, expanding from generating revenue from advertisements alone, to offering paid content such as movies and exclusive content produced by YouTube. It also offers YouTube Premium, a paid subscription option for watching content without ads. YouTube also approved creators to participate in Google's Google AdSens ...
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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 ...
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Space Launch System
The Space Launch System (SLS) is an American super heavy-lift expendable launch vehicle developed by NASA. As of 2022, SLS has the highest payload capacity of any rocket in operational service, as well as the greatest liftoff thrust of any rocket in operation. As the primary launch vehicle of the Artemis moon landing program, SLS is designed to launch the crewed Orion spacecraft on a trans-lunar trajectory. The first uncrewed launch, Artemis 1, took place on 16 November 2022. Development of SLS began in 2011, as a replacement for the retired Space Shuttle as well as the cancelled Ares I and Ares V launch vehicles. As a Shuttle-derived vehicle, the Space Launch System reuses hardware from the Space Shuttle program, including the Space Shuttle Solid Rocket Booster, solid rocket boosters and RS-25, RS-25 first stage engines. An original flight date of late 2016 was delayed by nearly 6 years. The SLS program has Space Launch System#Criticism, attracted criticism for such de ...
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Orion Artemis I Selfie 1
Orion () may refer to: Common meanings * Orion (constellation), named after the mythical hunter * Orion (mythology), a hunter in Greek mythology * Orion (spacecraft), NASA crew vehicle first launched in 2022 Arts and media Fictional entities Characters and species * Orion (character), a DC Comics character * Orion (''Star Trek''), a sentient alien species * Orion, code name of Stephen J. Bartowski on the television show ''Chuck'' * Orion, in the fighting game ''Brawlhalla'' * Orions, a race in the '' Starfire'' board game and book series * Orion, a character from ''Power Rangers Super Megaforce'' * Captain Orion, in the Japanese series '' X-Bomber'' Vessels * ''Orion'', a spaceplane in the film ''2001: A Space Odyssey'' * ''Orion'', a spaceship in '' Raumpatrouille Orion'' (''Space Patrol Orion'' in English), the first German science fiction television series * ''"Orion"''-class spaceship, on the television series '' Ascension'' Literature * ''Orion'', an 184 ...
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