DemonStar is a video game developed by Mountain King Studios and published in 1998. Considered an unofficial sequel to the studio's earlier Raptor: Call of the Shadows , it is a top-down vertically scrolling shooter set in outer space .
62-802: The player is a test pilot of a prototype starfighter , the RaptorX , launched by the Terran fleet. A space crime organization, known as the Alien Shogunate Xidus Armada, delivered a surprise attack to the Terran Fleet, destroying most of the Raptor fighters in the process. The few prototypes that were away being tested have survived. The player is tasked to battle through the Xidus Armada, destroy their ultimate weapon, codenamed
124-694: A sub-orbital spaceflight , a space vehicle enters space and then returns to the surface without having gained sufficient energy or velocity to make a full Earth orbit . For orbital spaceflights , spacecraft enter closed orbits around the Earth or around other celestial bodies . Spacecraft used for human spaceflight carry people on board as crew or passengers from start or on orbit ( space stations ) only, whereas those used for robotic space missions operate either autonomously or telerobotically . Robotic spacecraft used to support scientific research are space probes . Robotic spacecraft that remain in orbit around
186-599: A 15.2 metres (50 ft) CanadaArm1 , an upgraded version of which is used on the International Space Station . The heat shield (or Thermal Protection System ) of the orbiter, used to protect it from extreme levels of heat during atmospheric reentry and the cold of space, was made up of different materials depending on weight and how much heating a particular area on the shuttle would receive during reentry, which ranged from over 2,900 °F (1,600 °C) to under 700 °F (370 °C). The orbiter
248-563: A blunt shape, do not usually contain much more fuel than needed, and they do not possess wings unlike spaceplanes . They are the simplest form of recoverable spacecraft, and so the most commonly used. The first such capsule was the Vostok capsule built by the Soviet Union, that carried the first person in space, Yuri Gagarin . Other examples include the Soyuz and Orion capsules, built by
310-554: A liftoff thrust of 2,800,000 pounds-force (12 MN), which soon increased to 3,300,000 pounds-force (15 MN) per booster, and were fueled by a combination of PBAN and APCP , the Space Shuttle Orbiter , with 3 RS-25 engines that used a liquid oxygen / liquid hydrogen propellant combination, and the bright orange throwaway Space Shuttle external tank from which the RS-25 engines sourced their fuel. The orbiter
372-571: A planetary body are artificial satellites . To date, only a handful of interstellar probes , such as Pioneer 10 and 11 , Voyager 1 and 2 , and New Horizons , are on trajectories that leave the Solar System . Orbital spacecraft may be recoverable or not. Most are not. Recoverable spacecraft may be subdivided by a method of reentry to Earth into non-winged space capsules and winged spaceplanes . Recoverable spacecraft may be reusable (can be launched again or several times, like
434-417: A rendezvous with Intelsat-901 on 25 February 2020. It will remain with the satellite until 2025 before the satellite is moved to a final graveyard orbit and the vehicle does a rendezvous with another satellite. The other one launched on an Ariane 5 rocket on 15 August 2020. A spacecraft astrionics system comprises different subsystems, depending on the mission profile. Spacecraft subsystems are mounted in
496-678: A spacecraft of their own, the CST-100 , commonly referred to as Starliner , but a crewed flight is yet to occur. China developed, but did not fly Shuguang , and is currently using Shenzhou (its first crewed mission was in 2003). Except for the Space Shuttle and the Buran spaceplane of the Soviet Union, the latter of which only ever had one uncrewed test flight, all of the recoverable crewed orbital spacecraft were space capsules . The International Space Station , crewed since November 2000,
558-437: Is a list of fictional spacecraft, starships and exo-atmospheric vessels that have been identified by name in notable published works of fiction. The term " spacecraft " is mainly used to refer to spacecraft that are real or conceived using present technology. The terms " spaceship " and " starship " are generally applied only to fictional space vehicles, usually those capable of transporting people. Spaceships are often one of
620-652: Is a joint venture between Russia, the United States, Canada and several other countries. Uncrewed spacecraft are spacecraft without people on board. Uncrewed spacecraft may have varying levels of autonomy from human input; they may be remote controlled , remote guided or even autonomous , meaning they have a pre-programmed list of operations, which they will execute unless otherwise instructed. Many space missions are more suited to telerobotic rather than crewed operation, due to lower cost and lower risk factors. In addition, some planetary destinations such as Venus or
682-432: Is a vehicle that is designed to fly and operate in outer space . Spacecraft are used for a variety of purposes, including communications , Earth observation , meteorology , navigation , space colonization , planetary exploration , and transportation of humans and cargo . All spacecraft except single-stage-to-orbit vehicles cannot get into space on their own, and require a launch vehicle (carrier rocket). On
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#1732801743934744-443: Is an artificial satellite that relays and amplifies radio telecommunication signals via a transponder ; it creates a communication channel between a source transmitter and a receiver at different locations on Earth . Communications satellites are used for television , telephone , radio , internet , and military applications. Many communications satellites are in geostationary orbit 22,300 miles (35,900 km) above
806-526: Is the height required by the international organization Fédération Aéronautique Internationale to count as a spaceflight. This altitude is called the Kármán line . In particular, in the 1940s there were several test launches of the V-2 rocket , some of which reached altitudes well over 100 km. As of 2016, only three nations have flown crewed spacecraft: USSR/Russia, USA, and China. The first crewed spacecraft
868-626: Is to be replaced by expendable rockets such as the Space Launch System and ULA 's Vulcan rocket, as well as the commercial launch vehicles. Scaled Composites ' SpaceShipOne was a reusable suborbital spaceplane that carried pilots Mike Melvill and Brian Binnie on consecutive flights in 2004 to win the Ansari X Prize . The Spaceship Company built a successor SpaceShipTwo . A fleet of SpaceShipTwos operated by Virgin Galactic
930-910: The Star Wars universe, a " starfighter " is a blanket term for all small combat space craft, regardless of shields, hyperspace capability, weaponry (unless it carries none), armor, maneuverability and crew. "Snubfighter" (a term first used in Star Wars ), though no concise definition has been given, often refers to a fighter carrying shielding, secondary weapons systems such as proton torpedoes or concussion missiles, and being hyperspace capable. Starfighters sometimes bear mission designations similar to modern fighter aircraft, such as " strike fighter " and " space superiority fighter ". Galactic Republic Rebel Alliance and New Republic Galactic Empire and First Order Confederacy of Independent Systems Andromeda Halo Marvel Cinematic Universe Spacecraft A spacecraft
992-549: The Deep Space Network . A space telescope or space observatory is a telescope in outer space used to observe astronomical objects. Space telescopes avoid the filtering and distortion of electromagnetic radiation which they observe, and avoid light pollution which ground-based observatories encounter. They are divided into two types: satellites which map the entire sky ( astronomical survey ), and satellites which focus on selected astronomical objects or parts of
1054-617: The DemonStar , and conquer the Armada fleet. DemonStar is a shoot 'em up that features three weapons with levels of increasing power: proton lasers, ion cannons and plasma cannons, that can be side- or rear-mounted. The player may obtain additional power-ups that may be used as bombs or increase shields. The game features eighteen levels, a two-player local co-operative game mode, and a unlockable level editor. Mountain King Studios
1116-409: The International Space Station and Tiangong space station. Some spacecrafts can operate as both a crewed and uncrewed spacecraft. For example, the Buran spaceplane could operate autonomously but also had manual controls, though it never flew with crew onboard. Other dual crewed/uncrewed spacecrafts include: SpaceX Dragon 2 , Dream Chaser , and Tianzhou . A communications satellite
1178-440: The International Space Station : Russian Progress , American SpaceX Dragon 2 and Cygnus . Chinese Tianzhou is used to supply Tiangong space station . Space probes are robotic spacecraft that are sent to explore deep space, or astronomical bodies other than Earth. They are distinguished from landers by the fact that they work in open space, not on planetary surfaces or in planetary atmospheres. Being robotic eliminates
1240-850: The SpaceX Dragon and the Space Shuttle orbiters ) or expendable (like the Soyuz ). In recent years, more space agencies are tending towards reusable spacecraft. Humanity has achieved space flight, but only a few nations have the technology for orbital launches : Russia ( Roscosmos ), the United States ( NASA ), the member states of the European Space Agency , Japan ( JAXA ), China ( CNSA ), India ( ISRO ), Taiwan ( TSA ), Israel ( ISA ), Iran ( ISA ), and North Korea ( NADA ). In addition, several private companies have developed or are developing
1302-984: The VSS Enterprise . For other ships from Star Wars , Star Trek , Robotech , and other major franchises, see the separate lists linked below. (Planetary surface to orbit) "Space fighters" are fictional spacecraft analogous to fighter aircraft . They are popular as the subjects of flight simulators , movies and books. The following are some examples of notable space fighters from various media franchises : The Earth Alliance (Starfury fighters) The Minbari Federation The Narn Regime The Centauri Republic The Shadows The Vorlons The Twelve Colonies The Cylons The Earth Defense Directorate The Draconian Empire The United States Marine Corps The Chigs Terrestrial Extraterrestrial Tau'ri / Earth ( USAF fighters) The Goa'uld The Wraith The Ori In
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#17328017439341364-888: The Voskhod , Soyuz , flown uncrewed as Zond/L1 , L3 , TKS , and the Salyut and Mir crewed space stations . Other American crewed spacecraft include the Gemini spacecraft , the Apollo spacecraft including the Apollo Lunar Module , the Skylab space station, the Space Shuttle with undetached European Spacelab and private US Spacehab space stations-modules, and the SpaceX Crew Dragon configuration of their Dragon 2 . US company Boeing also developed and flown
1426-667: The dissolution of the USSR , prevented any further flights of Buran. The Space Shuttle was subsequently modified to allow for autonomous re-entry in case of necessity. Per the Vision for Space Exploration , the Space Shuttle was retired in 2011 mainly due to its old age and high cost of program reaching over a billion dollars per flight. The Shuttle's human transport role is to be replaced by SpaceX 's SpaceX Dragon 2 and Boeing 's CST-100 Starliner . Dragon 2's first crewed flight occurred on May 30, 2020. The Shuttle's heavy cargo transport role
1488-528: The equator , so that the satellite appears stationary at the same point in the sky; therefore the satellite dish antennas of ground stations can be aimed permanently at that spot and do not have to move to track the satellite. Others form satellite constellations in low Earth orbit , where antennas on the ground have to follow the position of the satellites and switch between satellites frequently. The high frequency radio waves used for telecommunications links travel by line of sight and so are obstructed by
1550-862: The American Orbiting Astronomical Observatory , OAO-2 launched in 1968, and the Soviet Orion 1 ultraviolet telescope aboard space station Salyut 1 in 1971. Space telescopes avoid the filtering and distortion ( scintillation ) of electromagnetic radiation which they observe, and avoid light pollution which ground-based observatories encounter. The best-known examples are Hubble Space Telescope and James Webb Space Telescope . Cargo spacecraft are designed to carry cargo , possibly to support space stations ' operation by transporting food, propellant and other supplies. Automated cargo spacecraft have been used since 1978 and have serviced Salyut 6 , Salyut 7 , Mir ,
1612-525: The CEO of SpaceX, estimated in a tweet that 8 launches would be needed to completely refuel a Starship in low Earth orbit , extrapolating this from Starship's payload to orbit and how much fuel a fully fueled Starship contains. To land on bodies without an atmosphere, such as the Moon, Starship will fire its engines and thrusters to slow down. The Mission Extension Vehicle is a robotic spacecraft designed to prolong
1674-421: The Moon, Mars, and potentially beyond. It is intended to enable long duration interplanetary flights for a crew of up to 100 people. It will also be capable of point-to-point transport on Earth, enabling travel to anywhere in the world in less than an hour. Furthermore, the spacecraft will be used to refuel other Starship vehicles to allow them to reach higher orbits to and other space destinations. Elon Musk ,
1736-500: The Solar System , these are Voyager 1 , Voyager 2 , Pioneer 10 , Pioneer 11 , and New Horizons . The identical Voyager probes , weighing 721.9 kilograms (1,592 lb), were launched in 1977 to take advantage of a rare alignment of Jupiter , Saturn , Uranus and Neptune that would allow a spacecraft to visit all four planets in one mission, and get to each destination faster by using gravity assist . In fact,
1798-517: The Soviet Union and NASA , respectively. Spaceplanes are spacecraft that are built in the shape of, and function as, airplanes . The first example of such was the North American X-15 spaceplane, which conducted two crewed flights which reached an altitude of over 100 kilometres (62 mi) in the 1960s. This first reusable spacecraft was air-launched on a suborbital trajectory on July 19, 1963. The first reusable orbital spaceplane
1860-554: The Sputnik launch was a single event, it marked the start of the Space Age . Apart from its value as a technological first, Sputnik 1 also helped to identify the upper atmospheric layer 's density, by measuring the satellite's orbital changes. It also provided data on radio -signal distribution in the ionosphere . Pressurized nitrogen in the satellite's false body provided the first opportunity for meteoroid detection. Sputnik 1
1922-521: The Sun as of August 2023. NASA provides real time data of their distances and data from the probe’s cosmic ray detectors. Because of the probe’s declining power output and degradation of the RTGs over time, NASA has had to shut down certain instruments to conserve power. The probes may still have some scientific instruments on until the mid-2020s or perhaps the 2030s. After 2036, they will both be out of range of
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1984-514: The addictiveness and intensity of its arcade-style gameplay. David Laprad of The Adrenaline Vault praised the game as "one of the most intense scrolling shooters I can ever recall playing...the level design is top-notch, and betrays the experience the developers have had designing this type of game." In reviewing the Secret Missions version, Stuart Campbell noted the game was a "tough, well-balanced, no-nonsense "shmup" that you can devote
2046-521: The back of a Boeing 747 SCA and gliding to deadstick landings at Edwards AFB, California . The first Space Shuttle to fly into space was Columbia , followed by Challenger , Discovery , Atlantis , and Endeavour . Endeavour was built to replace Challenger when it was lost in January 1986. Columbia broke up during reentry in February 2003. The first autonomous reusable spaceplane
2108-514: The curve of the Earth. The purpose of communications satellites is to relay the signal around the curve of the Earth allowing communication between widely separated geographical points. Communications satellites use a wide range of radio and microwave frequencies . To avoid signal interference, international organizations have regulations for which frequency ranges or "bands" certain organizations are allowed to use. This allocation of bands minimizes
2170-480: The different orbiters had differing weights and thus payloads, with Columbia being the heaviest orbiter, Challenger being lighter than Columbia but still heavier than the other three. The orbiter structure was mostly composed of aluminium alloy. The orbiter had seven seats for crew members, though on STS-61-A the launch took place with 8 crew onboard. The orbiters had 4.6 metres (15 ft) wide by 18 metres (59 ft) long payload bays and also were equipped with
2232-472: The game was an improvement of the resolution of Raptor by running in SVGA , but stated "there's a major trade-off: DemonStar always runs in a window, even (in) the so-called "full screen" mode, which simply crops out your desktop background with metallic textures". In 2023, a remastered version of the original DemonStar was released. Containing the same levels as the original, its audiovisual presentation
2294-410: The general spacecraft categories. This is a list of these spacecraft. Starship is a spacecraft and second stage under development by American aerospace company SpaceX . Stacked atop its booster, Super Heavy , it composes the identically named Starship super heavy-lift space vehicle . The spacecraft is designed to transport both crew and cargo to a variety of destinations, including Earth orbit,
2356-453: The key plot devices in science fiction . Numerous short stories and novels are built up around various ideas for spacecraft, and spacecraft have featured in many films and television series. Some hard science fiction books focus on the technical details of the craft. Some fictional spaceships have been referenced in the real world, notably Starship Enterprise from Star Trek which gave its name to Space Shuttle Enterprise and to
2418-426: The life on another spacecraft. It works by docking to its target spacecraft, then correcting its orientation or orbit. This also allows it to rescue a satellite which is in the wrong orbit by using its own fuel to move its target to the correct orbit. The project is currently managed by Northrop Grumman Innovation Systems. As of 2023, 2 have been launched. The first launched on a Proton rocket on 9 October 2019, and did
2480-636: The need for expensive, heavy life support systems (the Apollo crewed Moon landings required the use of the Saturn V rocket that cost over a billion dollars per launch, adjusted for inflation) and so allows for lighter, less expensive rockets. Space probes have visited every planet in the Solar System and Pluto , and the Parker Solar Probe has an orbit that, at its closest point, is in the Sun's chromosphere . There are five space probes that are escaping
2542-479: The odd blissful, brainless half-hour to." Many reviewers compared the game to its predecessor, Raptor , and the 1990 arcade video game Raiden . Stuart Campbell of PC Zone stated the game "follows the Raiden design template to a degree that verges on stalking." Gaming Entertainment Monthly assessed that their disappointment with DemonStar was due to high expectations "based on what Raptor offered in
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2604-491: The original engine and new music. Each Secret Missions title contains eight new levels. As a shareware title, DemonStar was packaged among other software, such as the Space Arcade Collection by Greenstreet Software, and Arcade Classics . DemonStar received mixed reviews upon release, with reviewers divided on the merits of the simplicity of its gameplay. Positive assessments of the game focused on
2666-455: The past". Common critiques included the lack of a save feature or a points system to upgrade the player's ship, as had been the case in Raptor . Negative reviews of DemonStar focused upon the low resolution for a game released in 1998. Richie Shoemaker of PC Zone stated "the viewing window is so tiny...you shouldn't have to switch resolution to enjoy a game". GameSpot acknowledged that
2728-471: The risk of signal interference. Cargo or resupply spacecraft are robotic spacecraft that are designed specifically to carry cargo , possibly to support space stations ' operation by transporting food, propellant and other supplies. Automated cargo spacecraft have been used since 1978 and have serviced Salyut 6 , Salyut 7 , Mir , the International Space Station and Tiangong space station. As of 2023, three different cargo spacecraft are used to supply
2790-519: The rocket that launched the probes (the Titan IIIE ) could not even send the probes to the orbit of Saturn , yet Voyager 1 is travelling at roughly 17 km/s (11 mi/s) and Voyager 2 moves at about 15 km/s (9.3 mi/s) kilometres per second as of 2023. In 2012, Voyager 1 exited the heliosphere, followed by Voyager 2 in 2018. Voyager 1 actually launched 16 days after Voyager 2 but it reached Jupiter sooner because Voyager 2
2852-454: The same way as a spaceship, as they coexist with numerous micro-organisms, and these micro-organisms are also hard to contain within a spaceship or spacesuit. Multiple space probes were sent to study Moon, the planets, the Sun, multiple small Solar System bodies (comets and asteroids). Special class of uncrewed spacecraft is space telescopes , a telescope in outer space used to observe astronomical objects. The first operational telescopes were
2914-504: The shuttle was a rather dangerous system, with fragile heat shielding tiles, some being so fragile that one could easily scrape it off by hand, often having been damaged in many flights. After 30 years in service from 1981 to 2011 and 135 flights, the shuttle was retired from service due to the cost of maintaining the shuttles, and the 3 remaining orbiters (the other two were destroyed in accidents) were prepared to be displayed in museums. Some spacecraft do not fit particularly well into any of
2976-583: The sky and beyond. Space telescopes are distinct from Earth imaging satellites , which point toward Earth for satellite imaging , applied for weather analysis , espionage , and other types of information gathering . A lander is a type of spacecraft that makes a soft landing on the surface of an astronomical body other than Earth . Some landers, such as Philae and the Apollo Lunar Module , land entirely by using their fuel supply, however many landers (and landings of spacecraft on Earth ) use aerobraking , especially for more distant destinations. This involves
3038-415: The spacecraft using a fuel burn to change its trajectory so it will pass through a planet (or a moon's) atmosphere. Drag caused by the spacecraft hitting the atmosphere enables it to slow down without using fuel, however this generates very high temperatures and so adds a requirement for a heat shield of some sort. Space capsules are a type of spacecraft that can return from space at least once. They have
3100-698: The technology for orbital launches independently from government agencies. The most prominent examples of such companies are SpaceX and Blue Origin . A German V-2 became the first spacecraft when it reached an altitude of 189 km in June 1944 in Peenemünde , Germany. Sputnik 1 was the first artificial satellite . It was launched into an elliptical low Earth orbit (LEO) by the Soviet Union on 4 October 1957. The launch ushered in new political, military, technological, and scientific developments; while
3162-420: The vicinity of Jupiter are too hostile for human survival. Outer planets such as Saturn , Uranus , and Neptune are too distant to reach with current crewed spaceflight technology, so telerobotic probes are the only way to explore them. Telerobotics also allows exploration of regions that are vulnerable to contamination by Earth micro-organisms since spacecraft can be sterilized. Humans can not be sterilized in
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#17328017439343224-503: Was Vostok 1 , which carried Soviet cosmonaut Yuri Gagarin into space in 1961, and completed a full Earth orbit. There were five other crewed missions which used a Vostok spacecraft . The second crewed spacecraft was named Freedom 7 , and it performed a sub-orbital spaceflight in 1961 carrying American astronaut Alan Shepard to an altitude of just over 187 kilometers (116 mi). There were five other crewed missions using Mercury spacecraft . Other Soviet crewed spacecraft include
3286-612: Was a spaceplane that was launched at NASA’s Kennedy Space Centre and landed mainly at the Shuttle Landing Facility , which is part of Kennedy Space Centre. A second launch site, Vandenberg Space Launch Complex 6 in California , was revamped so it could be used to launch the shuttles, but it was never used. The launch system could lift about 29 tonnes (64,000 lb) into an eastward Low Earth Orbit . Each orbiter weighed roughly 78 tonnes (172,000 lb), however
3348-458: Was completely revised. The remastered DemonStar features new high resolution graphics, a frame rate of up to 120 fps, a Tate mode for vertical monitors and a new soundtrack composed by the Danish sound artist Pfeffermouse . An optional "Legacy Mode" resembles the graphics of the 1998 DemonStar and features the original soundtrack by Bobby Prince. Military spacecraft in fiction This
3410-457: Was due to expensive refurbishment costs and the external tank being expended. Once a landing had occurred, the SRBs and many parts of the orbiter had to be disassembled for inspection, which was long and arduous. Furthermore, the RS-25 engines had to be replaced every few flights. Each of the heat shielding tiles had to go in one specific area on the orbiter, increasing complexity more. Adding to this,
3472-593: Was formed by lead developer Scott Host following his departure from Apogee Software to independently develop and self-publish titles. Development of DemonStar was completed by Scott Host and Kevin Blackman, with music composed by Robert Prince , who provided sound effects and music for the Doom series and other Apogee Software titles. DemonStar was re-released in 2003 as DemonStar: Secret Missions . Released in two parts, Secret Missions used an enhanced version of
3534-687: Was launched during the International Geophysical Year from Site No.1/5 , at the 5th Tyuratam range, in Kazakh SSR (now at the Baikonur Cosmodrome ). The satellite travelled at 29,000 kilometres per hour (18,000 mph), taking 96.2 minutes to complete an orbit, and emitted radio signals at 20.005 and 40.002 MHz While Sputnik 1 was the first spacecraft to orbit the Earth, other human-made objects had previously reached an altitude of 100 km, which
3596-606: Was manually operated, though an autonomous landing system was added while the shuttle was still on service. It had an in orbit maneouvreing system known as the Orbital Manoeuvring System, which used the hypergolic propellants monomethylhydrazine (MMH) and dinitrogen tetroxide , which was used for orbital insertion, changes to orbits and the deorbit burn. Though the shuttle’s goals were to drastically decrease launch costs, it did not do so, ending up being much more expensive than similar expendable launchers. This
3658-439: Was planned to begin reusable private spaceflight carrying paying passengers in 2014, but was delayed after the crash of VSS Enterprise . The Space Shuttle is a retired reusable Low Earth Orbital launch system. It consisted of two reusable Solid Rocket Boosters that landed by parachute, were recovered at sea, and were the most powerful rocket motors ever made until they were superseded by those of NASA’s SLS rocket, with
3720-403: Was taking a longer route that allowed it to visit Uranus and Neptune, whereas Voyager 1 did not visit Uranus or Neptune, instead choosing to fly past Saturn’s satellite Titan . As of August 2023, Voyager 1 has passed 160 astronomical units , which means it is over 160 times farther from the Sun than Earth is. This makes it the farthest spacecraft from the Sun. Voyager 2 is 134 AU away from
3782-530: Was the Buran -class shuttle , launched by the USSR on November 15, 1988, although it made only one flight and this was uncrewed. This spaceplane was designed for a crew and strongly resembled the U.S. Space Shuttle, although its drop-off boosters used liquid propellants and its main engines were located at the base of what would be the external tank in the American Shuttle. Lack of funding, complicated by
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#17328017439343844-578: Was the Space Shuttle orbiter . The first orbiter to fly in space, the Space Shuttle Columbia , was launched by the USA on the 20th anniversary of Yuri Gagarin 's flight, on April 12, 1981. During the Shuttle era, six orbiters were built, all of which have flown in the atmosphere and five of which have flown in space. Enterprise was used only for approach and landing tests, launching from
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