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
2.
Sentinel-1
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Sentinel-1 is a space mission funded by the European Union and carried out by the ESA within the Copernicus Programme, consisting of a constellation of two satellites. The payload of Sentinel-1 is a Synthetic Aperture Radar in C band that provides continuous imagery, on 12 March 2010, the European Space Agency and Thales Alenia Space signed a contract worth €270 million to build the second satellite of the Sentinel-1 pair. First Sentinel 1A arrived at launch site in Kourou, French Guiana on 25 February, sentinel-1A satellite was launched on 3 April 2014, by a Soyuz Rocket. Sentinel-1 will provide continuity of data from ERS and Envisat missions, with enhancements in terms of revisit, coverage, timeliness. A summary of applications are, Monitoring sea ice zones and the Arctic environment, the Sentinel-1 satellites are expected to make analysis of earthquakes using InSAR techniques quicker and simpler. Prime contractor of mission is Thales Alenia Space Italy, with whole system integration and also production of platform Spacecraft Management Unit and payload Data Storage. SAR instrument on payload is the responsibility of Astrium Gmbh, the Ground Segment prime contractor is Astrium with subcontractors Telespazio, WERUM, Advanced Computer Systems and Aresys
3.
Thales Alenia Space
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The company is Europes largest satellite manufacturer. Alcatel Alenia Space was established on June 1,2005 by the merger of Alcatel Space and Alenia Spazio and was owned by Alcatel-Lucent, the creation of the company was concurrent with the creation of Telespazio Holding. This too was a merger of Finmeccanica and Alcatel businesses, on April 5,2006 Alcatel agreed to sell its share of Alcatel Alenia Space to Thales Group. The European Union agreed in this operation on April 10,2007. The company built the Multi-Purpose Logistics Modules, which was used to transport cargo inside the Space Shuttle orbiters and they also built several modules for the International Space Station, those modules are Cupola, Columbus, Harmony, Tranquility and Leonardo. They currently build the vessels for the Automated Transfer Vehicle. In the mid-1990s, the United States stopped issuing licenses to companies to allow them to launch on Chinese launch vehicles out of fear that this would help Chinas military. In the face of this, Thales Alenia Space built the Chinasat-6B satellite with no components from the United States whatsoever and this allowed it to be launched on a Chinese launch vehicle without violating U. S. ITAR restrictions. The launch, on a Long March 3B rocket, was conducted on July 5,2007. Cannes Mandelieu Space Center Official website
4.
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
5.
Free-space optical communication
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Free-space optical communication is an optical communication technology that uses light propagating in free space to wirelessly transmit data for telecommunications or computer networking. Free space means air, outer space, vacuum, or something similar and this contrasts with using solids such as optical fiber cable or an optical transmission line. The technology is useful where the connections are impractical due to high costs or other considerations. Optical communications, in forms, have been used for thousands of years. The Ancient Greeks used an alphabetic system of signalling with torches developed by Cleoxenus, Democleitus and Polybius. In the modern era, semaphores and wireless solar telegraphs called heliographs were developed, in 1880, Alexander Graham Bell and his assistant Charles Sumner Tainter created the photophone, at Bells newly established Volta Laboratory in Washington, DC. Bell considered it his most important invention, the device allowed for the transmission of sound on a beam of light. On June 3,1880, Bell conducted the worlds first wireless transmission between two buildings, some 213 meters apart. Its first practical use came in military communication systems many decades later, German colonial troops used heliograph telegraphy transmitters during the Herero and Namaqua genocide starting in 1904, in German South-West Africa as did British, French, US or Ottoman signals. Optical telephone communications were tested at the end of the war, in addition, special blinkgeräts were used for communication with airplanes, balloons, and tanks, with varying success. A major technological step was to replace the Morse code by modulating optical waves in speech transmission, carl Zeiss, Jena developed the Lichtsprechgerät 80/80 that the German army used in their World War II anti-aircraft defense units, or in bunkers at the Atlantic Wall. The invention of lasers in the 1960s, revolutionized free space optics, military organizations were particularly interested and boosted their development. However the technology lost market momentum when the installation of fiber networks for civilian uses was at its peak. Many simple and inexpensive consumer remote controls use low-speed communication using infrared light and this is known as consumer IR technologies. Free-space point-to-point optical links can be implemented using infrared laser light, infrared Data Association technology is a very simple form of free-space optical communications. On the communications side the FSO technology is considered as a part of the Optical Wireless Communications applications, free-space optics can be used for communications between spacecraft. The demand for a high-speed and long range FSO system is apparent in the market place, in 2008, MRV Communications introduced a free-space optics -based system with a data rate of 10 Gbit/s initially claiming a distance of 2 km at high availability. This equipment is no longer available, before end-of-life, the products useful distance was changed down to 350 m, in April 2014, the company with Scientific and Technological Centre Fiord demonstrated the transmission speed 30 Gbit/s under laboratory conditions
6.
Europe
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Europe is a continent that comprises the westernmost part of Eurasia. Europe is bordered by the Arctic Ocean to the north, the Atlantic Ocean to the west, yet the non-oceanic borders of Europe—a concept dating back to classical antiquity—are arbitrary. Europe covers about 10,180,000 square kilometres, or 2% of the Earths surface, politically, Europe is divided into about fifty sovereign states of which the Russian Federation is the largest and most populous, spanning 39% of the continent and comprising 15% of its population. Europe had a population of about 740 million as of 2015. Further from the sea, seasonal differences are more noticeable than close to the coast, Europe, in particular ancient Greece, was the birthplace of Western civilization. The fall of the Western Roman Empire, during the period, marked the end of ancient history. Renaissance humanism, exploration, art, and science led to the modern era, from the Age of Discovery onwards, Europe played a predominant role in global affairs. Between the 16th and 20th centuries, European powers controlled at times the Americas, most of Africa, Oceania. The Industrial Revolution, which began in Great Britain at the end of the 18th century, gave rise to economic, cultural, and social change in Western Europe. During the Cold War, Europe was divided along the Iron Curtain between NATO in the west and the Warsaw Pact in the east, until the revolutions of 1989 and fall of the Berlin Wall. In 1955, the Council of Europe was formed following a speech by Sir Winston Churchill and it includes all states except for Belarus, Kazakhstan and Vatican City. Further European integration by some states led to the formation of the European Union, the EU originated in Western Europe but has been expanding eastward since the fall of the Soviet Union in 1991. The European Anthem is Ode to Joy and states celebrate peace, in classical Greek mythology, Europa is the name of either a Phoenician princess or of a queen of Crete. The name contains the elements εὐρύς, wide, broad and ὤψ eye, broad has been an epithet of Earth herself in the reconstructed Proto-Indo-European religion and the poetry devoted to it. For the second part also the divine attributes of grey-eyed Athena or ox-eyed Hera. The same naming motive according to cartographic convention appears in Greek Ανατολή, Martin Litchfield West stated that phonologically, the match between Europas name and any form of the Semitic word is very poor. Next to these there is also a Proto-Indo-European root *h1regʷos, meaning darkness. Most major world languages use words derived from Eurṓpē or Europa to refer to the continent, in some Turkic languages the originally Persian name Frangistan is used casually in referring to much of Europe, besides official names such as Avrupa or Evropa
7.
European Union
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The European Union is a political and economic union of 28 member states that are located primarily in Europe. It has an area of 4,475,757 km2, the EU has developed an internal single market through a standardised system of laws that apply in all member states. Within the Schengen Area, passport controls have been abolished, a monetary union was established in 1999 and came into full force in 2002, and is composed of 19 EU member states which use the euro currency. The EU operates through a system of supranational and intergovernmental decision-making. The EU traces its origins from the European Coal and Steel Community, the community and its successors have grown in size by the accession of new member states and in power by the addition of policy areas to its remit. While no member state has left the EU or its antecedent organisations, the Maastricht Treaty established the European Union in 1993 and introduced European citizenship. The latest major amendment to the basis of the EU. The EU as a whole is the largest economy in the world, additionally,27 out of 28 EU countries have a very high Human Development Index, according to the United Nations Development Programme. In 2012, the EU was awarded the Nobel Peace Prize, through the Common Foreign and Security Policy, the EU has developed a role in external relations and defence. The union maintains permanent diplomatic missions throughout the world and represents itself at the United Nations, the World Trade Organization, the G7, because of its global influence, the European Union has been described as an emerging superpower. After World War II, European integration was seen as an antidote to the nationalism which had devastated the continent. 1952 saw the creation of the European Coal and Steel Community, the supporters of the Community included Alcide De Gasperi, Jean Monnet, Robert Schuman, and Paul-Henri Spaak. These men and others are credited as the Founding fathers of the European Union. In 1957, Belgium, France, Italy, Luxembourg, the Netherlands and West Germany signed the Treaty of Rome and they also signed another pact creating the European Atomic Energy Community for co-operation in developing nuclear energy. Both treaties came into force in 1958, the EEC and Euratom were created separately from the ECSC, although they shared the same courts and the Common Assembly. The EEC was headed by Walter Hallstein and Euratom was headed by Louis Armand, Euratom was to integrate sectors in nuclear energy while the EEC would develop a customs union among members. During the 1960s, tensions began to show, with France seeking to limit supranational power, Jean Rey presided over the first merged Commission. In 1973, the Communities enlarged to include Denmark, Ireland, Norway had negotiated to join at the same time, but Norwegian voters rejected membership in a referendum
8.
Synthetic-aperture radar
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Synthetic aperture radar is a form of radar that is used to create two- or 3-dimensional images of objects, such as landscapes. SAR uses the motion of the radar antenna over a region to provide finer spatial resolution than conventional beam-scanning radars. SAR is typically mounted on a platform such as an aircraft or spacecraft. The distance the SAR device travels over a target in the time taken for the pulses to return to the antenna creates the large synthetic antenna aperture. To create a SAR image, successive pulses of waves are transmitted to illuminate a target scene. The pulses are transmitted and the echoes received using a single beam-forming antenna, as the SAR device on board the aircraft or spacecraft moves, the antenna location relative to the target changes with time. The properties of SAR can be described as having high resolution capability which is independent of flight altitude, SAR also have a great day and night imaging capability considering their own illumination. SAR images have wide applications in sensing and mapping of the surfaces of both the Earth and other planets. Volcano and earthquake monitoring is a part of differential interferometry and it is also useful in environment monitoring like oil spills, flooding, urban growth, global change and military surveillance which includes strategic policy and tactical assessment. SAR can also be implemented as inverse SAR by observing a moving target over a time with a stationary antenna. A Synthetic Aperture Radar is a radar mounted on a moving platform. Electromagnetic waves are transmitted and reflected echoes are collected, digitized and stored by the radar antenna for later processing. As transmission and reception occur at different time, they map to different positions, the well ordered combination of the received signals builds a virtual aperture that is much longer than the physical antenna length. This is why it is named synthetic aperture, giving it the property of being an imaging radar, the 3D processing is done in two steps, the azimuth and range direction are focussed for the generation of 2D high resolution images. After which a digital model is used to measure the phase differences between complex images which is determined from different look angles to recover the height information. This height information, along with the coordinates provided by 2-D SAR focusing. The first step requires only standard processing algorithms, for the step a additional pre-processing stage such as image co-registration. In addition to this, multiple baselines can be used to extend 3D imaging to the time dimension, the SAR algorithm, as given here, applies to phased arrays generally
9.
French Guiana
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French Guiana, officially called Guiana, is an overseas department and region of France, located on the north Atlantic coast of South America in the Guyanas. It borders Brazil to the east and south, and Suriname to the west. Its 83,534 km2 area has a low population density of only 3 inhabitants per km2, with half of its 244,118 inhabitants in 2013 living in the metropolitan area of Cayenne. By land area, it is the second largest region of France, both the region and the department have been ruled since December 2015 by a single assembly within the framework of a new territorial collectivity, the French Guiana Territorial Collectivity. This assembly, the French Guiana Assembly, has replaced the regional council and departmental council. The French Guiana Assembly is in charge of regional and departmental government, the area was originally inhabited by Native Americans. The first French establishment is recorded in 1503 but the French presence didnt really become durable until 1643, Guiana then became a slave colony and saw its population increase until the official abolition of slavery at the time of the French revolution. During World War II, the Guianan Félix Éboué was one of the first to stand behind General de Gaulle as early as June 18,1940, Guiana officially rallied Free France in 1943. It definitively abandoned its status as a colony and became again a French department in 1946, de Gaulle, who became president, decided to establish the Guiana Space Center in 1965. It is now operated by the CNES, Arianespace and the European Space Agency, several thousand Hmong refugees from Laos migrated to French Guiana in the late 1970s and early 1980s. Nowadays fully integrated in the French central state, Guiana is a part of the European Union, the region is the most prosperous territory in South America with the highest GDP per capita. A large part of Guianas economy derives from the presence of the Guiana Space Centre, as elsewhere in France, the official language is French, but each ethnic community has its own language, of which Guianan Creole is the most widely spoken. Guiana is derived from an Amerindian language and means land of many waters, French Guiana and the two larger countries to the north and west, Guyana and Suriname, are still often collectively referred to as the Guianas and constitute one large shield landmass. French Guiana was originally inhabited by people, Kalina, Arawak, Emerillon, Galibi, Palikur, Wayampi. The French attempted to create a colony there in the 18th century in conjunction with its settlement of some other Caribbean islands, in this penal colony, the convicts were sometimes used as butterfly catchers. During its existence, France transported approximately 56,000 prisoners to Devils Island, fewer than 10% survived their sentence. In addition, in the nineteenth century, France began requiring forced residencies by prisoners who survived their hard labor. A Portuguese-British naval squadron took French Guiana for the Portuguese Empire in 1809 and it was returned to France with the signing of the Treaty of Paris in 1814
10.
BBC
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The British Broadcasting Corporation is a British public service broadcaster. It is headquartered at Broadcasting House in London, the BBC is the worlds oldest national broadcasting organisation and the largest broadcaster in the world by number of employees. It employs over 20,950 staff in total,16,672 of whom are in public sector broadcasting, the total number of staff is 35,402 when part-time, flexible, and fixed contract staff are included. The BBC is established under a Royal Charter and operates under its Agreement with the Secretary of State for Culture, Media and Sport. The fee is set by the British Government, agreed by Parliament, and used to fund the BBCs radio, TV, britains first live public broadcast from the Marconi factory in Chelmsford took place in June 1920. It was sponsored by the Daily Mails Lord Northcliffe and featured the famous Australian Soprano Dame Nellie Melba, the Melba broadcast caught the peoples imagination and marked a turning point in the British publics attitude to radio. However, this public enthusiasm was not shared in official circles where such broadcasts were held to interfere with important military and civil communications. By late 1920, pressure from these quarters and uneasiness among the staff of the licensing authority, the General Post Office, was sufficient to lead to a ban on further Chelmsford broadcasts. But by 1922, the GPO had received nearly 100 broadcast licence requests, John Reith, a Scottish Calvinist, was appointed its General Manager in December 1922 a few weeks after the company made its first official broadcast. The company was to be financed by a royalty on the sale of BBC wireless receiving sets from approved manufacturers, to this day, the BBC aims to follow the Reithian directive to inform, educate and entertain. The financial arrangements soon proved inadequate, set sales were disappointing as amateurs made their own receivers and listeners bought rival unlicensed sets. By mid-1923, discussions between the GPO and the BBC had become deadlocked and the Postmaster-General commissioned a review of broadcasting by the Sykes Committee and this was to be followed by a simple 10 shillings licence fee with no royalty once the wireless manufactures protection expired. The BBCs broadcasting monopoly was made explicit for the duration of its current broadcast licence, the BBC was also banned from presenting news bulletins before 19.00, and required to source all news from external wire services. Mid-1925 found the future of broadcasting under further consideration, this time by the Crawford committee, by now the BBC under Reiths leadership had forged a consensus favouring a continuation of the unified broadcasting service, but more money was still required to finance rapid expansion. Wireless manufacturers were anxious to exit the loss making consortium with Reith keen that the BBC be seen as a service rather than a commercial enterprise. The recommendations of the Crawford Committee were published in March the following year and were still under consideration by the GPO when the 1926 general strike broke out in May. The strike temporarily interrupted newspaper production and with restrictions on news bulletins waived the BBC suddenly became the source of news for the duration of the crisis. The crisis placed the BBC in a delicate position, the Government was divided on how to handle the BBC but ended up trusting Reith, whose opposition to the strike mirrored the PMs own
11.
YouTube
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YouTube is an American video-sharing website headquartered in San Bruno, California. The service was created by three former PayPal employees—Chad Hurley, Steve Chen, and Jawed Karim—in February 2005, Google bought the site in November 2006 for US$1.65 billion, YouTube now operates as one of Googles subsidiaries. Unregistered users can watch videos on the site, while registered users are permitted to upload an unlimited number of videos. Videos deemed potentially offensive are available only to registered users affirming themselves to be at least 18 years old, YouTube earns advertising revenue from Google AdSense, a program which targets ads according to site content and audience. YouTube was founded by Chad Hurley, Steve Chen, and Jawed Karim, Hurley had studied design at Indiana University of Pennsylvania, and Chen and Karim studied computer science together at the University of Illinois at Urbana-Champaign. Karim could not easily find video clips of either event online, Hurley and Chen said that the original idea for YouTube was a video version of an online dating service, and had been influenced by the website Hot or Not. YouTube began as a venture capital-funded technology startup, primarily from an $11.5 million investment by Sequoia Capital between November 2005 and April 2006, YouTubes early headquarters were situated above a pizzeria and Japanese restaurant in San Mateo, California. The domain name www. youtube. com was activated on February 14,2005, the first YouTube video, titled Me at the zoo, shows co-founder Jawed Karim at the San Diego Zoo. The video was uploaded on April 23,2005, and can still be viewed on the site, YouTube offered the public a beta test of the site in May 2005. The first video to reach one million views was a Nike advertisement featuring Ronaldinho in November 2005. Following a $3.5 million investment from Sequoia Capital in November, the site grew rapidly, and in July 2006 the company announced that more than 65,000 new videos were being uploaded every day, and that the site was receiving 100 million video views per day. The site has 800 million unique users a month and it is estimated that in 2007 YouTube consumed as much bandwidth as the entire Internet in 2000. The choice of the name www. youtube. com led to problems for a similarly named website, the sites owner, Universal Tube & Rollform Equipment, filed a lawsuit against YouTube in November 2006 after being regularly overloaded by people looking for YouTube. Universal Tube has since changed the name of its website to www. utubeonline. com, in October 2006, Google Inc. announced that it had acquired YouTube for $1.65 billion in Google stock, and the deal was finalized on November 13,2006. In March 2010, YouTube began free streaming of certain content, according to YouTube, this was the first worldwide free online broadcast of a major sporting event. On March 31,2010, the YouTube website launched a new design, with the aim of simplifying the interface, Google product manager Shiva Rajaraman commented, We really felt like we needed to step back and remove the clutter. In May 2010, YouTube videos were watched more than two times per day. This increased to three billion in May 2011, and four billion in January 2012, in February 2017, one billion hours of YouTube was watched every day
12.
Sentinel-2
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It consists of two identical satellites, Sentinel-2A and Sentinel-2B. At high latitudes, Sentinel-2 swath overlap and some regions will be observed twice or more every 5 days, the planned orbit is Sun synchronous at 786 km altitude,14.3 revolutions per day, with a 10,30 a. m. descending node. This local time was selected as a compromise between minimizing cloud cover and ensuring suitable Sun illumination and it is close to the Landsat local time and matches SPOTs, allowing the combination of Sentinel-2 data with historical images to build long-term time series. The two satellites will work on opposite sides of the orbit, the launch of the first satellite, Sentinel-2A, occurred 23 June 2015 at 01,52 UTC on a Vega launch vehicle. Sentinel-2B was launched on 7 March 2017 at 01,49 UTC, the Sentinel-2 satellites will each carry a single multi-spectral instrument with 13 spectral channels in the visible/near infrared and short wave infrared spectral range. It has a 150 mm aperture and a three-mirror anastigmat design with a length of about 600 mm. The mirrors are rectangular and made of carbide, a similar technology to those on the Gaia mission. Sentinel-2 will serve a range of applications related to Earths land surface. The mission will provide information for agricultural and forestry practices. Satellite images will be used to various plant indices such as leaf area chlorophyll. This is particularly important for effective yield prediction and applications related to Earth’s vegetation, as well as monitoring plant growth, Sentinel-2 can be used to map changes in land cover and to monitor the worlds forests. It will also provide information on pollution in lakes and coastal waters, images of floods, volcanic eruptions and landslides contribute to disaster mapping and help humanitarian relief efforts. Sentinel-2s multi-spectral imager undertakes systematic acquisition in a single observation mode, Level-1B, Top of atmosphere radiances in sensor geometry. Level-1B is composed of granules, one represents the sub-image one of the 12 detectors in the across track direction. Each Level-1B granule has a volume of approximately 27 MB. Level-1B products require expert knowledge of orthorectification techniques, level-1C, Top of atmosphere reflectances in fixed cartographic geometry. Level-1C images are a set of tiles of 100 km2, each of which is approximately 500 MB and these products contain applied radiometric and geometric corrections. Level-2A, Bottom of atmosphere reflectances in cartographic geometry and this product is currently processed on the user side by using a processor running on ESA’s Sentinel-2 Toolbox
