1.
European Space Agency
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The European Space Agency is an intergovernmental organisation of 22 member states, dedicated to the exploration of space. Established in 1975 and headquartered in Paris, France, ESA has a staff of about 2,000. The main European launch vehicle Ariane 5 is operated through Arianespace with ESA sharing in the costs of launching, after World War II, many European scientists left Western Europe in order to work with the United States. The meeting was attended by representatives from eight countries, including Harrie Massey. The Western European nations decided to have two different agencies, one concerned with developing a system, ELDO, and the precursor of the European Space Agency. The latter was established on 20 March 1964 by an agreement signed on 14 June 1962, from 1968 to 1972, ESRO launched seven research satellites. ESA in its current form was founded with the ESA Convention in 1975, ESA has 10 founding member states, Belgium, Denmark, France, Germany, Italy, the Netherlands, Spain, Sweden, Switzerland and the United Kingdom. These signed the ESA Convention in 1975 and deposited the instruments of ratification by 1980, during this interval the agency functioned in a de facto fashion. ESA launched its first major scientific mission in 1975, Cos-B, ESA joined NASA in the IUE, the worlds first high-orbit telescope, which was launched in 1978 and operated very successfully for 18 years. A number of successful Earth-orbit projects followed, and in 1986 ESA began Giotto, its first deep-space mission, to study the comets Halley and Grigg–Skjellerup. Hipparcos, a mission, was launched in 1989 and in the 1990s SOHO, Ulysses. Recent scientific missions in co-operation with NASA include the Cassini–Huygens space probe, as the successor of ELDO, ESA has also constructed rockets for scientific and commercial payloads. Ariane 1, launched in 1979, brought mostly commercial payloads into orbit from 1984 onward, the successor launch vehicle of Ariane 5, the Ariane 6 is already in the definition stage and is envisioned to enter service in the 2020s. The beginning of the new millennium saw ESA become, along with agencies like NASA, JAXA, ISRO, CSA and Roscosmos, one of the major participants in scientific space research. Although ESA had relied on co-operation with NASA in previous decades, especially the 1990s, changed circumstances led to decisions to rely more on itself, a 2011 press issue thus stated, Russia is ESAs first partner in its efforts to ensure long-term access to space. ESA maintains its scientific and research projects mainly for astronomy-space missions such as Corot, launched on 27 December 2006 and this is the reason space exploration is an integral part of overall space activities. It has always been so, and it will be more important in the future. ESA describes its work in two overlapping ways, For the general public the various fields of work are described as Activities, Member states participate to varying degrees in the mandatory and optional space programmes
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Guiana Space Centre
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The Guiana Space Centre or, more commonly, Centre Spatial Guyanais is a French and European spaceport to the northwest of Kourou in French Guiana. The European Space Agency, the French space agency CNES, and this was the spaceport used by the ESA to send supplies to the International Space Station using the Automated Transfer Vehicle. The location was selected in 1964 to become the spaceport of France, in 1975, France offered to share Kourou with ESA. Commercial launches are bought also by non-European companies, ESA pays two thirds of the spaceports annual budget and has also financed the upgrades made during the development of the Ariane launchers. Since April 4,2017, the centre has been occupied by 30 labor union leaders in the midst of the 2017 social unrest in French Guiana, Kourou is located approximately 500 kilometres north of the equator, at a latitude of 5°10. The near-equatorial launch location provides an advantage for launches to low-inclination Earth orbits compared to launches from spaceports at higher latitude, the proximity to the equator also makes maneuvering satellites for geosynchronous orbits simpler and less costly. Originally built in the 1960s under the name of CECLES, the ELV pad located at 5. 236°N52. 775°W /5.236, one Europa-II was launched from the site, before the programme was cancelled. The pad was demolished, and subsequently rebuilt as the first launch complex for Ariane rockets, renamed ELA, it was used for Ariane 1 and Ariane 2 and 3 launches until being retired in 1989. It was again refurbished for the Vega with the first launch performed on 13 February 2012, the ELA2 pad, located at 5. 232°N52. 776°W /5.232, -52.776 had been used for Ariane 4 launches until 2003. ELA3 has been active for Ariane 5 launches since 1996 and this facility is located at 5. 239°N52. 768°W /5.239, -52.768 and covers an area of 21 square kilometres. ESA has built ELS at 5. 305°N52. 834°W /5.305, the first Soyuz launch from ELS was postponed several times, but launched on October 21,2011. ELS is located on the territory of Sinnamary commune,27 km from Kourou harbor and it is 10 km north of the site used for the Ariane 5 launches. Russia will use the Guiana Space Centre in addition to Baikonur Cosmodrome, the Guiana location has the significant benefit of greatly increased payload capability, owing to the near equatorial position. A Soyuz rocket with a 1.7 tonnes to geostationary transfer orbit performance from Baikonur, the ELS project is being co-funded by Arianespace, ESA, and the European Union, with CNES being the prime contractor. The project has a projected cost of approximately €320 million, where €120 million are allocated for modernizing the Soyuz vehicle, the official opening of the launch site construction occurred on 27 February 2007. Excavation work however, had begun several months beforehand. By October 2010,18 launch contracts had been signed, Arianespace has ordered 24 launchers from Russian industry. On October 21,2011, two Galileo IOV-1 & IOV-2 satellites were launched using a Soyuz-ST rocket, in the first Russian Soyuz vehicle ever launched from Europes Spaceport in French Guiana, astrium assembles each Ariane 5 launcher in the Launcher Integration Building
3.
CNES
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The Centre national détudes spatiales is the French government space agency. Its headquarters are located in central Paris and it is under the supervision of the French Ministries of Defence and it operates from the Toulouse Space Center and Guiana Space Centre, but also has payloads launched from space centres operated by other countries. The president of CNES is Jean-Yves Le Gall, CNES is member of Institute of Space, its Applications and Technologies. CNES benefits from the second largest national budget allocated to space, CNES was established under President Charles de Gaulle in 1961. CNES was responsible for the training of French astronauts, until the last active CNES astronauts transferred to the European Space Agency in 2001. As of January 2015, CNES is working with Germany and a few governments to start a modest research effort with the hope to propose a LOX/methane reusable launch vehicle by mid-2015. If built, flight testing would not start before approximately 2026. Hammaguir missile range built in Algeria,1963 Cats launched into space via Véronique rockets. 1965 First French satellite put in orbit,1969 French Guiana Space Centre completed. Commercial competition in space is fierce, so launch services must be tailored to space operators’ needs, the new versions of Ariane 5 can launch large satellites or perform dual launches while the Vega and Soyuz-2 are small and medium-lift launchers. CNES is taking part in the Galileo navigation programme alongside the European Union, in addition to Spot and the future Pleiades satellites, CNES is working for the defence community as prime contractor for the Helios satellites. France’s contribution to the International Space Station is giving French scientists the opportunity to perform experiments in microgravity. The CNES is studying formation flying, a technique whereby several satellites fly components of a much heavier, CNES is collaborating with other space agencies in a number of projects. Joint missions with NASA result in PARASOL and CALIPSO satellites, CNES plays a major role in the construction and operation of the Soil Moisture and Ocean Salinity satellite. In December 2006, CNES announced that it would publish its UFO archive online by late January or mid-February, most of the 6,000 reports have been filed by the public and airline professionals. Jacques Arnould, an official for the French Space Agency, said that the data had accumulated over a 30-year period and that they were often reported to the Gendarmerie. In the last two decades of the 20th century, France was the country whose government paid UFO investigators, employed by CNESs UFO section GEPAN, later known as SEPRA. On March 22,2007, CNES released its UFO files to the public through its website, the CNES has several tracking stations
4.
Solid-propellant rocket
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A solid-propellant rocket or solid rocket is a rocket with a rocket engine that uses solid propellants. The earliest rockets were solid-fuel rockets powered by gunpowder, they were used in warfare by the Chinese, Indians, Mongols and Persians, all rockets used some form of solid or powdered propellant up until the 20th century, when liquid-propellant rockets offered more efficient and controllable alternatives. Solid rockets are used today in model rockets and on larger applications for their simplicity and reliability. Since solid-fuel rockets can remain in storage for periods, and then reliably launch on short notice. Solids are, however, frequently used as boosters to increase payload capacity or as spin-stabilized add-on upper stages when higher-than-normal velocities are required. Solid rockets are used as launch vehicles for low Earth orbit payloads under 2 tons or escape payloads up to 500 kilograms. A simple solid rocket motor consists of a casing, nozzle, grain, the grain behaves like a solid mass, burning in a predictable fashion and producing exhaust gases. The nozzle dimensions are calculated to maintain a design chamber pressure, once ignited, a simple solid rocket motor cannot be shut off, because it contains all the ingredients necessary for combustion within the chamber in which they are burned. More advanced solid rocket motors can not only be throttled but also be extinguished, also, pulsed rocket motors that burn in segments and that can be ignited upon command are available. Design begins with the total impulse required, which determines the fuel/oxidizer mass, grain geometry and chemistry are then chosen to satisfy the required motor characteristics. The following are chosen or solved simultaneously, the results are exact dimensions for grain, nozzle, and case geometries, The grain burns at a predictable rate, given its surface area and chamber pressure. The chamber pressure is determined by the orifice diameter and grain burn rate. Allowable chamber pressure is a function of casing design, the length of burn time is determined by the grain web thickness. The grain may or may not be bonded to the casing, case-bonded motors are more difficult to design, since the deformation of the case and the grain under flight must be compatible. Common modes of failure in rocket motors include fracture of the grain, failure of case bonding. All of these produce an increase in burn surface area and a corresponding increase in exhaust gas production rate and pressure. Another failure mode is casing seal failure, seals are required in casings that have to be opened to load the grain. Once a seal fails, hot gas will erode the escape path and this was the cause of the Space Shuttle Challenger disaster
5.
Liquid-propellant rocket
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A liquid-propellant rocket or liquid rocket is a rocket engine that uses liquid propellants. This permits the use of low-mass propellant tanks, resulting in a mass ratio for the rocket. An inert gas stored in a tank at a pressure is sometimes used instead of pumps in simpler small engines to force the propellants into the combustion chamber. These engines may have a mass ratio, but are usually more reliable. And are therefore used widely in satellites for orbit maintenance, some designs are throttleable for variable thrust operation and some may be restarted after a previous in-space shutdown. Liquid propellants are used in hybrid rockets, in which a liquid oxidizer is generally combined with a solid fuel. This seminal treatise on astronautics was published in 1903, but was not distributed outside Russia until years later, german V-2 inventor Wernher von Braun considered Paulet one of the fathers of aeronautics. The National Air & Space Museum in Washington, D. C. has a plaque honoring the memory of Paulet. He was the only known developer of liquid-propellant rocket engine experiments in the 19th century, however, he did not publish his work. In 1927 he wrote a letter to a newspaper in Lima, historians of early rocketry experiments, among them Max Valier, Willy Ley, and John D. Clark, have given differing amounts of credence to Paulets report. Paulet described laboratory tests of, but did not claim to have launched a liquid rocket. Wernher von Braun, in his book World History of Aeronautics states, Pedro Paulet was in Paris in those years, experimenting with his tiny two-and-a-half kilogram motor, by this act, Paulet should be considered the pioneer of the liquid fuel propulsion motor. Further, in his History of Rocketry and Space Travel, von Braun recognizes that by his efforts, Paulet helped man reach the Moon. The rocket, which was dubbed Nell, rose just 41 feet during a 2. 5-second flight that ended in a cabbage field, goddard proposed liquid propellants about fifteen years earlier and began to seriously experiment with them in 1921. In Germany, engineers and scientists became enthralled with liquid-fuel rockets and this amateur rocket group, the VfR, included Wernher von Braun, who became the head of the army research station that secretly built the V-2 rocket weapon for the Nazis. The German-Romanian Hermann Oberth published a book in 1922 suggesting the use of liquid propellants, after World War II the American government and military finally seriously considered liquid-propellant rockets as weapons and began to fund work on them. The Soviet Union did likewise, and thus began the Space Race, bipropellant liquid rockets generally use a liquid fuel, such as liquid hydrogen or a hydrocarbon fuel such as RP-1, and a liquid oxidizer, such as liquid oxygen. The engine may be a rocket engine, where the fuel and oxidizer
6.
Airbus Defence and Space
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Airbus Defence and Space is a division of Airbus Group responsible for defence and aerospace products and services. The division was formed in January 2014 during the restructuring of European Aeronautic Defence and Space, and comprises the former Airbus Military, Astrium. It is the second largest space company after Boeing and one of the top ten defence companies in the world. Airbus Defence and Space has its headquarters in Toulouse, France, and is led by Dirk Hoke. The company is divided into three sections, Military Aircraft, Space Systems, and Communication-Intelligence-Security, with its presence in 35 countries, the company employs 40,000 people from 86 nationalities and contributes to 21% of Airbus Group revenues. In 2015 Airbus ranked 100th on the Fortune Global 500 list, the two companies envisaged including the French company Aérospatiale, the other major European aerospace company, but only after its privatisation. The first stage of integration was seen as the transformation of Airbus from a consortium of British Aerospace, DASA, Aérospatiale. The merger of British Aerospace and MES to form BAE Systems was announced on 19 January 1999, DASA and the Spanish aircraft company Construcciones Aeronáuticas SA agreed to merge on 11 June 1999. On 14 October 1999 DASA agreed to merge with Aérospatiale-Matra to create the European Aeronautic Defence and Space Company,10 July 2000 was Day One for the new company which became the worlds second-largest aerospace company after Boeing and the second-largest European arms manufacturer after BAE Systems. In January 2001 Airbus Industrie was transformed from an inherently inefficient consortium structure to a joint stock company, with legal. On 16 June 2003 EADS acquired BAEs 25 % share in Astrium, EADS paid £84 million, however due to the lossmaking status of the company BAE invested an equal amount for restructuring. It was subsequently renamed EADS Astrium, and had the divisions Astrium Satellites, Astrium Space Transportation, on 1 July 2003 EADS Defence & Security Systems was founded with the merger of the activities of missile systems, defence electronics, military aircraft and telecommunications of the EADS Group. Tom Enders became the first CEO of the new division, the predecessor company was established in January 1999 as the Airbus Military Company SAS to manage the Airbus A400M project, taking over from the Euroflag consortium. In May 2003, the company was restructured as Airbus Military Sociedad Limitada prior to the execution of the production contract, the Military Transport Aircraft Division was a division of EADS which designs, manufactures and commercialises EADS-CASA light and medium transport aircraft, and headquartered in Madrid, Spain. In 1999 was Construcciones Aeronáuticas SA in the EADS Group incorporated, in Spain it was still referred to as EADS-CASA. The division manufactured tanker, transport and mission aircraft including Airbus A330 MRTT, Airbus A400M, CASA C-212 Aviocar, CASA/IPTN CN-235, after the merger, it also acquired the production of Eurofighter Typhoon, which was earlier under Cassidian. Eurocopter, which was earlier under Airbus Military, was reorganized as Airbus Helicopters, Astrium was formed in 2000 by the merger of Matra Marconi Space with the space division of DaimlerChrysler Aerospace AG and Computadores Redes e Ingeniería SA. Henceforth Astrium was a joint venture between EADS and BAE Systems, on 16 June 2003 the minority shareholder, BAE Systems, sold its 25% share to EADS, making EADS the sole shareholder
7.
Kourou
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Kourou is a commune in French Guiana, an overseas region and department of France located in South America. In addition to being a district in French Guiana, it is also the main town in that district. Within the Kourou district lies the Guiana Space Centre, France, some 60 km northwest of the French Guyanese capital Cayenne the Kourou River empties into the Atlantic Ocean. At the mouth of this sits the town of Kourou. There are three lakes within the city limits, Lake Bois Diable, Lake Marie-Claire, and Lake Bois Chaudat. Long white sand beaches and some rocky outcrops line the towns ocean coast, the town had a fast-growing population of 25,918 inhabitants at the 2007 census. Much of it burned down in a fire in 2006, Guiana in general has a high level of crime compared to the rest of Frances départements, Kourou has an average of two armed robberies a day. A march protesting the high level of insecurity felt by most of the population was held in Kourou on 27 October 2006, shopkeepers of Chinese descent in particular are often targeted by armed robbers, their cash registers emptied and some products stolen. Kourou is the port of departure for those going to the îles du Salut and it is also common for many to go up the river in canoes on weekends to camp in the forest. The Guiana Space Centre, where the European Space Agency starts missions, is located a little behind, part of the town and the islands are closed during rocket launches. Not much is known of the pre-colonial era, the area was mostly populated by Kalina, or Galibi before the arrival of the French in the late 17th century. There is a place not far from the town called les Roches Gravées, vicente Yáñez Pinzón sailed along most of the north coast of South America and passed by the current location of Kourou in 1500. The Society of Jesus was disbanded in 1762, however, the mission at Kourou being abandoned by the Jesuits, the engineers Mentelle and Tugny designed the layout of the future town. This resulted in the called the Bourg, around the Church of Saint Catherine. That same year,1763, as agreed in the Treaty of Paris, having lost their largest and richest colony, the French decided to send a large expedition to Guiana, commanded by Choiseul. Around 10,000 to 12,000 people, mostly Frenchmen, tempted by stories of an El Dorado on the side of the ocean. The small town, surrounded by marshes and rainforest, was unprepared for such an influx of people. Those remaining fled to the îles du Salut, free of mosquitoes due to constant winds, previously they had been known as the îles du Diable, and one of the islands retains the name to this day
8.
Liquid hydrogen
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Liquid hydrogen is the liquid state of the element hydrogen. Hydrogen is found naturally in the molecular H2 form, one common method of obtaining liquid hydrogen involves a compressor resembling a jet engine in both appearance and principle. Liquid hydrogen is used as a concentrated form of hydrogen storage. As in any gas, storing it as liquid takes less space than storing it as a gas at temperature and pressure. However, the density is very low compared to other common fuels. Once liquefied, it can be maintained as a liquid in pressurized, liquid hydrogen consists of 99. 79% parahydrogen,0. 21% orthohydrogen. In 1885 Zygmunt Florenty Wróblewski published hydrogens critical temperature as 33 K, critical pressure,13.3 atmospheres, hydrogen was liquefied by James Dewar in 1898 by using regenerative cooling and his invention, the vacuum flask. The first synthesis of the stable form of liquid hydrogen, parahydrogen, was achieved by Paul Harteck. Room–temperature hydrogen consists mostly of the orthohydrogen form, practical H2–O2 rocket engines run fuel-rich so that the exhaust contains some unburned hydrogen. This reduces combustion chamber and nozzle erosion and it also reduces the molecular weight of the exhaust which can actually increase specific impulse despite the incomplete combustion. Liquid hydrogen can be used as the fuel for an internal combustion engine or fuel cell, various submarines and concept hydrogen vehicles have been built using this form of hydrogen. Due to its similarity, builders can sometimes modify and share equipment with systems designed for LNG, however, because of the lower volumetric energy, the hydrogen volumes needed for combustion are large. Unless LH2 is injected instead of gas, hydrogen-fueled piston engines usually require larger fuel systems, unless direct injection is used, a severe gas-displacement effect also hampers maximum breathing and increases pumping losses. Liquid hydrogen is used to cool neutrons to be used in neutron scattering. Since neutrons and hydrogen nuclei have similar masses, kinetic energy exchange per interaction is maximum, finally, superheated liquid hydrogen was used in many bubble chamber experiments. The first thermonuclear bomb, Ivy Mike, used liquid deuterium, the product of its combustion with oxygen alone is water vapor, which can be cooled with some of the liquid hydrogen. Since water is harmless to the environment, an engine burning it can be considered zero emissions, liquid hydrogen also has a much higher specific energy than gasoline, natural gas, or diesel. The density of hydrogen is only 70.99 g/L
9.
Safran Aircraft Engines
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Snecma S. A. or Safran Aircraft Engines is a French multinational aircraft and rocket engine manufacturer headquartered in Courcouronnes, France. Alone or in partnership, Snecma designs, develops, produces and markets engines for civil and military aircraft, the company also offers a complete range of engine support services to airlines, armed forces and other operators. Snecma is a subsidiary of Safran, Snecma used to be an acronym for Société nationale détudes et de construction de moteurs daviation until 27 April 2004. Snecma was formed in 1945 with German BMW jet engine technology when the large French aero engine firm Gnome & Rhône was nationalised, in 1961, Snecma and Bristol Siddeley agreed to a joint venture to produce the power plant for Concorde, which would become the Rolls-Royce/Snecma Olympus 593. The main body of the came from the Bristol Olympus with the refinements being the addition of the variable intakes necessary for supersonic flight. In 1968, Snecma took control of Hispano-Suiza, Socata and Bugatti, in a subsequent reorganisation, all aero-engine maintenance services would be grouped as Socata-Snecma. In 1970, Messier and Snecma agreed to merge their landing gear businesses, the following year, Messier-Hispano was formed in which Snecma held a stake. Snecma took full control of Messier-Hispano in 1973, in 1977, the landing gear business was further consolidated by the creation of Messier-Hispano-Bugatti. Snecma and General Electric created a joint venture in 1974, CFM International, testing of FADEC, a joint development of the two companies, began in 1985. In 1990, Snecma announced its participation in the General Electric GE90 engine programme, Messier-Dowty was formed in 1994 following the merger of the landing gear businesses of Snecma and the British TI Group. In 1997 Snecma acquired 100 per cent of Société européenne de propulsion, in 1998, Snecma took full control of Messier-Dowty. In 1999, Snecma Services was created to consolidate all maintenance, repair, in 2000, Snecma became a holding company and the propulsion business was reformed as Snecma Moteurs. Later in the year Snecma acquired Labinal, along with its Turbomeca, in 2001, Hurel-Hispano was created to consolidate the groups engine nacelle and thrust reverser businesses. In 2005, Snecma merged with Sagem to form SAFRAN, Snecma was divided, with the companys subsidiaries contributing to the propulsion and equipment divisions of the new group. Snecma moteurs was then renamed Snecma, in 2010, Snecma and GE formed CFM Materials as a joint venture. In 2016, Snecma was renamed Safran Aircraft Engines, the companys major civil aircraft engine is the CFM International CFM56. Produced by a partnership between Snecma and General Electric, CFM56s power more than 4,900 aircraft around the world, Snecma is also the main partner for the General Electric CF6-80 and GE90 programs. This engine is one of two available to power the Airbus A380
10.
Launch vehicle
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In spaceflight, a launch vehicle or carrier rocket is a rocket used to carry a payload from Earths surface into outer space. A launch system includes the launch vehicle, the launch pad, Earth orbital launch vehicles typically have at least two stages, and sometimes as many as four or more. Expendable launch vehicles are designed for one-time use and they usually separate from their payload and disintegrate during atmospheric reentry. In contrast, reusable vehicles are designed to be recovered intact. The Space Shuttle was a part of a vehicle with components used for multiple orbital spaceflights. SpaceX has developed a rocket launching system to successfully bring back a part—the first stage—of their Falcon 9 and launch it again. A fully reusable VTVL design is planned for all parts of the ITS launch vehicle, Launch vehicles are often classified by the amount of mass they can carry into orbit. For example, a Proton rocket can lift 22,000 kilograms into low Earth orbit, Launch vehicles are also characterized by their number of stages. Rockets with as many as five stages have been successfully launched, additionally, launch vehicles are very often supplied with boosters supplying high early thrust, normally burning with other engines. Boosters allow the engines to be smaller, reducing the burnout mass of later stages to allow larger payloads. Other frequently reported characteristics of vehicles are the launching nation or space agency. For example, the European Space Agency is responsible for the Ariane V, many launch vehicles are considered part of a historical line of vehicles of same or similar name, e. g. the Atlas V is the latest Atlas rocket. A small-lift launch vehicle is capable of lifting up to 2,000 kg of payload into low Earth orbit, a medium-lift launch vehicle is capable of lifting 2,000 to 20,000 kg of payload into LEO. A heavy-lift launch vehicle is capable of lifting 20,000 to 50,000 kg of payload into LEO, a super-heavy lift vehicle is capable of lifting more than 50,000 kg of payload into LEO. It refers to its 1,500 kg to LEO Vega launch vehicle as light lift, sounding rockets have long been used for brief, inexpensive unmanned space and microgravity experiments. Current human-rated suborbital launch vehicles include SpaceShipOne and the upcoming SpaceShipTwo, minimizing air drag requires a reasonably high ballistic coefficient, a ratio of length to diameter greater than ten. This generally results in a vehicle that is at least 20 m long. Leaving the atmosphere as early on in the flight as possible provides a velocity loss due to air drag of around 300 m/s, Launch vehicles of sufficient size are capable of launching payloads smaller than their orbital capability, to the Moon or beyond
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Liquid oxygen
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Liquid oxygen—abbreviated LOx, LOX or Lox in the aerospace, submarine and gas industries—is one of the physical forms of elemental oxygen. Liquid oxygen has a blue color and is strongly paramagnetic. Liquid oxygen has a density of 1.141 g/cm3 and is cryogenic with a point of 54.36 K. Because of its nature, liquid oxygen can cause the materials it touches to become extremely brittle. Liquid oxygen is also a powerful oxidizing agent, organic materials will burn rapidly and energetically in liquid oxygen. Further, if soaked in liquid oxygen, some such as coal briquettes, carbon black, etc. can detonate unpredictably from sources of ignition such as flames. Petrochemicals, including asphalt, often exhibit this behavior, the tetraoxygen molecule was first predicted in 1924 by Gilbert N. Lewis, who proposed it to explain why liquid oxygen defied Curies law. Modern computer simulations indicate that there are no stable O4 molecules in liquid oxygen, O2 molecules do tend to associate in pairs with antiparallel spins. Conversely, liquid nitrogen or liquid air can be oxygen-enriched by letting it stand in air, atmospheric oxygen dissolves in it. In commerce, liquid oxygen is classified as a gas and is widely used for industrial and medical purposes. Liquid oxygen is obtained from the oxygen found naturally in air by fractional distillation in an air separation plant. Liquid oxygen is a cryogenic liquid oxidizer propellant for spacecraft rocket applications, usually in combination with liquid hydrogen. Liquid oxygen is useful in this role because it creates a specific impulse. It was used in the very first rocket applications like the V2 missile and Redstone, R-7 Semyorka, Atlas boosters, many modern rockets use liquid oxygen, including the main engines on the now-retired Space Shuttle. U. S. Army has long recognized the importance of liquid oxygen. In 1985 it started a program of building its own facilities at all major consumption bases. By 1845, Michael Faraday had managed to liquefy most gases then known to exist, six gases, however, resisted every attempt at liquefaction and were known at the time as permanent gases. They were oxygen, hydrogen, nitrogen, carbon monoxide, methane, in 1877, Louis Paul Cailletet in France and Raoul Pictet in Switzerland succeeded in producing the first droplets of liquid air
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Ariane 5
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Ariane 5 is a European heavy lift launch vehicle that is part of the Ariane rocket family, an expendable launch system used to deliver payloads into geostationary transfer orbit or low Earth orbit. Ariane 5 rockets are manufactured under the authority of the European Space Agency, airbus Defence and Space is the prime contractor for the vehicles, leading a consortium of other European contractors. Ariane 5 is operated and marketed by Arianespace as part of the Ariane programme, the rockets are launched by Arianespace from the Guiana Space Centre in French Guiana. Ariane 5 succeeded Ariane 4, but was not derived from it directly, Ariane 5 has been refined since the first launch in successive versions, G, G+, GS, ECA, and most recently, ES. ESA originally designed Ariane 5 to launch the Hermes spaceplane, two satellites can be mounted using a SYLDA carrier. Three main satellites are possible depending on size using SPELTRA, up to eight secondary payloads, usually small experiment packages or minisatellites, can be carried with an ASAP platform. As of July 2015 Arianespace has signed contracts for Ariane 5 ECA launches up till 2023, on 14 February 2017, Ariane 5 performed its 77th consecutive successful mission since 2003. Ariane 5’s cryogenic H173 main stage is called the EPC. It consists of a large tank 30.5 metres high with two compartments, one for liquid oxygen and one for hydrogen, and a Vulcain 2 engine at the base with a vacuum thrust of 1,390 kilonewtons. The H173 EPC weighs about 189 tonnes, including 175 tonnes of propellant, after the main cryogenic stage runs out of fuel, it can re-enter the atmosphere for an ocean splashdown. Attached to the sides are two P241 solid rocket boosters, each weighing about 277 tonnes full and delivering a thrust of about 7,080 kilonewtons and they are fueled by a mix of ammonium perchlorate and aluminum fuel and HTPB. They each burn for 130 seconds before being dropped into the ocean, the most recent attempt was for the first Ariane 5 ECA mission. One of the two boosters was successfully recovered and returned to the Guiana Space Center for analysis, prior to that mission, the last such recovery and testing was done in 2003. The French M51 SLBM shares a substantial amount of technology with these boosters, in February 2000 the suspected nose cone of an Ariane 5 booster washed ashore on the South Texas coast, and was recovered by beachcombers before the government could get to it. The second stage is on top of the stage and below the payload. The Ariane 5 G used the EPS, which is fueled by monomethylhydrazine and it also has 10 tonnes of storable propellants. The EPS was improved for use on the Ariane 5 G+, GS, Ariane 5 ECA uses the ESC, which is fueled by liquid hydrogen and liquid oxygen. The EPS upper stage is capable of multiple ignitions, first demonstrated during flight V26 which was launched on 5 October 2007 and this was purely to test the engine, and occurred after the payloads had been deployed
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