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South Korea Categories: Countries; government and resources Beginning in the late twentieth century, South Korea’s economy rapidly expanded, ranking second interna- tionally in growth, because of industrial development and income from such resources as semiconductors. Because South Korea lacks sufficient metal and min- eral resources, government and business representa- tives seek agreements with North Korean officials to extract and use resources from that country’s abun- dant deposits. The Country South Korea, an East Asian country, is located on a peninsula divided by the Korean Demilitarized Zone (DMZ) that separatesSouthKorea from North Korea. As of 2004, South Korea’s economy had attained a value of $1 trillion. In 2007, South Korea’s economy was the third largest in Asia and the thirteenth largest globally. South Korea’s landscape is characterized mostly by mountains, plains, andvalleys, with theHan, Nakdong, Yeongsan, and Geum rivers representing main interior water resources. South Korea includes approximately three thousand islands of varying sizes and distances from thepeninsula.Pusan, the country’s biggest port, accesses the Korea Strait on South Korea’s southern coast, and the port at Inch’o n on South Korea’s west- ern coast is next to the Yellow Sea. The country is di- vided into nine provinces and seven metropolitan cit- ies. TheDMZ containsdiverse naturalresources, which are protected from human appropriation. Coal South Koreangovernmentofficialsencourage extrac- tion of indigenous coal resources in an attempt to decrease imports of oil and other fuels to generate energy. Among the world’s top-five oil importers, South Korea relied on oil for 50 percent of its energy needs in the early twenty-first century and also pur- chased large amounts of natural gas. Coal provides almost one-fourth of South Korea’s energy resources. South Korean coal deposits, mostly in the form of anthracite, consist of 1.4 billion metric tons, with less than one-third of that reserve considered accessible for extraction. Korean coalfields occur in provinces stretching from the southwestern to the northeastern regions of the country. Sites that produced signifi - cant amounts of coal include fields at Mungyeong, Danyang, Samcheok, Honam, Boeun, and Yeong- weol. Additional places with coal deposits are Gimpo, Yeoncheon, and Chungnam. South Korea’s coal industry has functioned since the 1920’s, withelevated oil prices in the 1970’s result- ing in its highest production rates in the twentieth century. Approximately 350 mines produced 24 mil- lion tons annually until the late 1980’s, when lower oil prices, higher incomes, and consumers’ preferences for natural gasand clean energy sources resulted in the South Korean government’s demanding the closure of most mines. The field at Samcheok continued to sup- ply coal in the 1990’s despite economic fluctuations. In the early twenty-first century, South Korean offi- cials emphasized that coal was an abundant native re- source that could reinforce that country’s security by providing energy that could not be accessed or controlled by foreign nations. They prioritized this resource instead of focusing on developing renew- able solar, hydropower, and wind energies. The gov- ernment’s Korea Mining Promotion Corporation (KMPC) improved mines with technology and ma- chinery near coal-rich fields. Investors also established private mines at Dongwon and Samchuk in Kangwo n Province. Despite these efforts, South Korean industrializa- tion dramatically increased energy needs and resulted in South Korean power companies importing coal from China, Australia, and the United States. Korean coal supplied merely 3.2 million metric tons in 2004, approximately 4 percent of the 82.2 million metric tons ofcoal-generated energyin SouthKorea thatyear. Tungsten The South Korean tungsten deposit at Sangdong in Kangwo n Province provided approximately 90 per- cent of the country’s tungsten for domestic and ex- port uses. Tungsten is a useful industrial metal, and aerospace technology often incorporates tungsten because it is not altered in extreme heat situations. Tungsten is found in deposits of several compounds such aswolframite and scheelite,located inthe moun- tainous regions of South Korea. Operating since 1947, the Sangdong mine has sup- plied a large percentage of tungsten availableto inter- national markets. The Chongyang mine is another source of South Korean tungsten. Both mines also ex - tract molybdenum. South Korean manufacturers use Global Resources South Korea • 1127 1128 • South Korea Global Resources South Korea: Resources at a Glance Official name: Republic of Korea Government: Republic Capital city: Seoul Area: 38,505 mi 2 ; 98,720 km 2 Population (2009 est.): 48,508,972 Language: Korean Monetary unit: South Korean won (KRW) Economic summary: GDP composition by sector (2008 est.): agriculture, 3%; industry, 39.5%; services, 57.6% Natural resources: coal, tungsten, graphite, molybdenum, lead, hydropower potential Land use (2005): arable land, 16.58%; permanent crops, 2.01%; other, 81.41% Industries: electronics, telecommunications, automobile production, chemicals, shipbuilding, steel Agricultural products: rice, root crops, barley, vegetables, fruit, cattle, pigs, chickens, milk, eggs, fish Exports (2008 est.): $433.5 billion Commodities exported: semiconductors, wireless telecommunications equipment, motor vehicles, computers, steel, ships, petrochemicals Imports (2008 est.): $427.4 billion Commodities imported: machinery, electronics and electronic equipment, oil, steel, transport equipment, organic chemicals, plastics Labor force (2008 est.): 24.35 million Labor force by occupation (2007): agriculture, 7.2%; industry, 25.1%; services, 67.7% Energy resources: Electricity production (2008 est.): 440 billion kWh Electricity consumption (2008 est.): 385.1 billion kWh Electricity exports (2008 est.): 0 kWh Electricity imports (2008 est.): 0 kWh Natural gas production (2007 est.): 640 million m 3 Natural gas consumption (2007 est.): 37 billion m 3 Natural gas exports (2007 est.): 0 m 3 Natural gas imports (2007 est.): 34.4 billion m 3 Natural gas proved reserves ( Jan. 2008 est.): 50 billion m 3 Oil production (2007 est.): 20,970 bbl/day Oil imports (2008): 2.37 million bbl/day Oil proved reserves: N/A Source: Data from The World Factbook 2009. Washington, D.C.: Central Intelligence Agency, 2009. Notes: Data are the most recent tracked by the CIA. Values are given in U.S. dollars. Abbreviations: bbl/day = barrels per day; GDP = gross domestic product; km 2 = square kilometers; kWh = kilowatt-hours; m 3 = cubic meters; mi 2 = square miles. Seoul China South Korea North Korea Japan East China Sea Sea of Japan Yellow Sea Pacific Ocean tungsten for electronic components such as lightbulb filaments, wires, and tubes in appliances and ma- chines and mix tungsten with carbide to create effec- tive cutting devices and industrial tools. Jewelry, par- ticularly wedding bands, is often crafted from tungsten because of the metal’s durability. South Korea led world exports of tungsten until China began exporting large quantities of that metal in 1993, resulting in prices dropping. Unable to profit from tungsten, South Korea ceased extracting ore containing tungsten in the early 1990’s. In 2006, the Sangdong mine resumed operations when it was bought by the Canadian company Oriental Minerals. The government’s Korea Resources Corporation (KORES) estimated reserves totaled 85,700 metric tons of tungsten trioxide and 63,500 metric tons of molybdenum. Molybdenum Molybdenum is a crucial resource incorporated in stainless steel manufacture at steel mills.South Korea, ranking fifth in global steel production in 2007, sought to extract indigenous sources of molybdenum in an attempt to stop importing that resource from rival molybdenum producers Chile and China, which have the largest molybdenum deposits internationally. China stated it would limit exports and licenses regu- lating that market, intensifying South Korean efforts to mine molybdenum domestically. South Korean government officials also envisioned exporting surplus molybdenum to steel mills in Tai- wan, Japan, and other countries to generate income as the value of that resource rose. In 2006, KORES and KTC Korea Company, which trades metals, co- operated to finance and build South Korea’s initial smelter for molybde- num at Yeosu. Thatfacility, which be- gan operating thefollowing year, was capable of processing 6,000 metric tons of molybdenum annually. At that time, South Korea’s molybde- num smelter was the seventh biggest internationally. The Yeosu smelter provided 35percent ofmolybdenum needed by South Korean steel mills. South Korea’s molybdenum mine at Uljin, containing approximately 3.7 million metric tons of molybdenum, shipped 670 tons of that resource yearly to the Yeosu smelter with plans to increase the amount of ore extracted so pro- duction could double. KORES stated that representa- tives would seek additional molybdenum deposits in South Korea, and build mines, in addition to those at Sangdong and Chongyang, to extract that resource. In 2007, Metal Bulletin reported international prices for molybdenum had risen 25 percent from the previ- ous year and expected global demand to increase 5.2 percent annually, offering South Korea a lucrative ex- port opportunity. Minerals South Korea lost direct access to approximately 90 percent of the peninsula’s mineral resources when the 1953 armistice divided the peninsula at the 38th Parallel after the Korean War. Prior to division, most mining and industrial activity had occurred in the northern half of the peninsula, where the majority of Korean natural resources were located. Geologists have stated that there are approximately 220 mineral types in North Korea, ranging from coal to uranium, which have reserves worth $2 trillion. North Korean mineral resources included 2.7 billion metric tons of iron ore, 1.08 million metric tons of nickel, and 907 metric tons of gold, almost twenty-five times greater than South Korean mineral resources. South Korea Global Resources South Korea • 1129 South Korean workers unloadblocks of zincfrom a North Korean cargo ship.North Korea has more natural resources than SouthKorea, butthe latter hasbetter processing facilities. (Jo Yong-Hak/Reuters/Landov) spent $13 billion in 2006 importing minerals to fulfill manufacturers’ needs. Despite political differences, officials from North and SouthKorea discussedthepossibility ofSouth Ko- rea providing North Korea with money if South Kore- ans could invest in North Korean mines to acquire magnesite, zinc,and other specified mineraldeposits. North Korea did not have sufficient mining expertise and technological devices to extract those resources. In the early twenty-first century, the Kaesong Indus- trial Park was built north of the DMZ. South Korean businesses invested in manufacturing at that facility’s factories. Industrial representatives from both coun- tries metseveral times at P’yo ngyang, North Korea,re- garding South Korea’s desire to receive northern nat- ural resources. In 2007, Han-ho Lee, representing KORES, and Un-up Chung, director of the North Korean Inter- Korean Economic Cooperation Association, dis- cussed an agreement involving the North Korean South Hwanghae Province lead mine. Thetwo Koreas arranged to extract black lead resources, of which 725.6 to 907 metric tons would be shipped to South Korea and distributed to buyers by Wonjin Corpora- tion. The representatives approved another lead-min- ing collaboration to acquire that mineral resource lo- cated in Pungcheon. They also discussed a mutual project in South Hwanghae Province at Shinwon to start extractinglimestone froma minelocated there. By December, 2007, the South Korean Ministry of Commerce, Industry and Energy had requested sur- veys of North Korea’s geological resources to aid South Korean investors interested in northern miner- als. South Korean officials noted that mines in western North Korea in the Haeju-Nampo area had phos- phate, limestone, and graphite deposits. In the east- ern part of North Korea, South Hamgyeong Prov- ince’s Dancheon mines and power plants interested South Korean companies. North Korea sent 500 met- ric tons of zinc to the Inch’o n port in 2007, and an- other shipment of the same amount in 2008, for a total of $2.4 million worth of the north’s minerals to compensate SouthKorea forits economicassistance. Graphite South Korean miners extract approximately 2 million metric tons annually from graphite deposits south of the DMZ, including seams in the Kyongsang district. This resource enables South Korea to be the top producer ofgraphite inthe world.Because this graph - ite has minimal carbon, South Korea sells most of it to Japanese foundries instead of supplying it to do- mestic manufacturers. Seeking better-quality graph- ite sources, South Korean representatives secured agreements with North Korean officials regarding graphite deposits above the 38th parallel. In 2003, KORES contracted for a 50 percent share with the North Korean Kwangmyung Trading Com- pany, investing $5.77 million and supplying equip- ment to operate a $10.2 million graphite-processing plant near the Jeongchon mine in South Hwanghae Province, whichheld 5.67 million metrictons of graph- ite ore and could produce 2,721 metric tons yearly. South Korea’s half of thatamountwould fulfill 20 per- cent ofthe country’s domesticneeds forgraphite over a fifteen-year period. The South Hwanghae factory started producing graphite in 2007. In November, 2007, North Korean representatives shippedapproximately 180metric tons of graphite from the North Korean port at Nampo to Inch’o n. The joint graphite-mining effort stalled the next year for several reasons, including stricter poli- cies regarding North Korea enacted by South Korean president Myung-bak Lee in 2008. Insufficient elec- tricity in North Korea to power graphite mining, the north’s restrictions involving transporting goods across the border, and their nuclear missile tests dis- rupted resource-mining agreements. Semiconductors South Korea expands its economy with technology and electronics exports and has consistently been a global leader in the production of semiconductor resources. Semiconductors are South Korea’s most valuable export; the country ships more semiconduc- tors internationally than televisions and automobiles. Samsung Electronics, Hyundai Electronics Industrial Company, and GoldStar (now LG Electronics) domi- nated semiconductor manufacturing in the late 1980’s. Those manufacturers worked with the govern- ment’s Electronics and Telecommunications Research Institute to create a semiconductor witha four-megabit random access memory (RAM) chip, enabling stor- age of four million binary units, revolutionary at that time, matching semiconductor achievements in the United States and Japan. In 1996, South Korean semi- conductor companies manufactured 17 percent of dynamic RAM semiconductors in the world. South Korea’s semiconductor resources generated more than $10 billion annually during the 1990’s. 1130 • South Korea Global Resources By the early twenty-first century, South Korea was producing the greatest quantity of semicon- ductors globally, with Samsung’s semiconductor plant at Kiheung andHynix Semiconductor man- ufacturing most of the world’s memory chips. South Korean engineers seek to improve semi- conductor design, speed, and capacity to com- pete with regional rivals Japan, China, and India and secure electronics markets worldwide. Since 2004, the Consortium of Advanced Semiconduc- tor Research has focused on enhancing this tech- nology in South Korea and expanding produc- tion of semiconductors designed specifically for vehicles. South Korean semiconductors earned $17.34 billion during the first eight months of 2004. The next year, Samsung Electronics was credited with producing 20 percent of South Ko- rean exports. The economic recession of 2008 and 2009 im- pacted South Korea’s semiconductor industry. Starting in July, 2008, South Korean exports of semiconductors decreased as the result of several factors, including a surplus of semiconductors and economic problems in the United States and Europe, which are both major markets for South Korean computer products. South Korean offi- cials suggested the country could regain its in- ternational status for exporting semiconductors within two years by improving the quality and ca- pabilities of South Korean semiconductors. In 2009, Samsung Electronics represented 30.3 per- cent of semiconductors produced, ranking first internationally; Hynix, ranked second globally, manufactured 19.1 percent of semiconductors. Other Resources South Korean gold and silver deposits and mines are located on Muguk and Gasado Island. Several hun- dred thousand metric tons of copper are refined an- nually at Onsan and Changhang smelters. Fisheries had represented 1 percent of South Korean exports until a shift in focus to technology exports occurred, resulting in less commercial fishing. In 2009, South Korea invested $17.8 billion in a river restoration project to improve water resources. Programs to re- plenish forests damaged in twentieth century wars contributed to increased timber resources for eco- nomic gains. Because South Korea’s native resources for energy are limited,the country relieson nuclear andthermal plants to produce power. In 2006, nuclearpower plants produced 36.6 percent of electricity, representing 379.73 billion kilowatt-hours of electricity generated. South Korea used the fifth most nuclear energy inter- nationally in 2007. A tidal power plant built in 2009 at the lake near Sihwa produced the same amount of power annually as obtained from 862,000 barrels of oil, and a bigger tidal power plant, designed to be the largest in the world, was planned for construction on Ganghwa Island. South Korean officials encourage photovoltaic cell manufacturing and power plants to supplement energy resources and export for profit. By 2008, South Korea was ranked fourth globally in photovoltaic technology. In the early twenty-first cen- tury,South Korea produced thesecond most powerin Asia andwas rankedsixth inglobal powerproduction. Elizabeth D. Schafer Global Resources South Korea • 1131 Hana Micron employees develop semiconductors used mainly by Sam- sung Electronics. South Korea is a leading producer of semiconductors. (Bloomberg via Getty Images) Further Reading Fackler, Martin. “Big Dreams forNorth Korean Indus- trial Park.” The New York Times, August 21, 2008, p. C3. “In the Global War for Resources, Korea Could Be Left Behind.” Business Korea 26, no. 297 (March, 2009): 16-17. Kim, Sang-Wan, etal.“Analysis of Ground Subsidence in Coal Mining Area Using SAR Interferometry.” Geosciences Journal 12,no. 3(September,2008): 277- 284. Mathews, John A., and Dong-Sung Cho. Tiger Technol- ogy: The Creation of a Semiconductor Industry in East Asia. NewYork:Cambridge UniversityPress, 2007. Web Site Republic of Korea (official Web site) http://www.korea.net See also: Coal; Hydroenergy; Resources as a source of international conflict; Semiconductors; Silicon. Space resources Categories: Ecological resources; obtaining and using resources; social, economic, and political issues The vastness beyond Earth’s thin atmosphere is rich in extraterrestrial resources. Microgravity technologies have been developed to take advantage of those re- sources. Solar energy captured on Earth or in space is used to generate electrical power. Applications in communications, global monitoring, and the Global Positioning System have been developed to improve the quality of human life. Satellites document planetary biosphere changes that occur naturally or from human activity. Background Launching Sputnik 1 in 1957, theSovietUnion began a racetodevelop technology thatprovided routine ac- cess to space. The region from low Earth orbit (LEO) outward to geostationary Earth orbit (GEO) is con- centrated with satellitesthat peer regularly atEarth or with telescopes looking outward. The region between LEO and GEO is the most utilized with regard to space resources. There, some resources have present commercial profitability. Space beyond GEO remains largely for scientific exploration and resource specu- lation. Communication Satellites An object in GEO revolves about Earth’s center in ex- actly one day. This means that as Earth rotates on its axis, a GEO object appears to hang directly overhead. Geostationary position is 35,800 kilometers above Earth’s surface. Early communications satellites were only put in LEO. The next push was to install operational systems in GEO to relay television images, data, and tele- phone signals around the world. LEO satellites have regained a share of communications traffic. These cross an observer’s sky in ten to twenty minutes, so a constellation of satellites is required for continuous reception. Because LEO satellites are only 500 to 1,400 kilometers above Earth’s surface, they can be reached with a signal much less powerful than one re- quired for a geostationary satellite. Consequently, ground stations that provide uplinks and downlinks for LEO satellites can be modest. Thus, LEO satellites can provide portable telephone service and data links to underdeveloped areas. Weather and Climate Observing Satellites Geostationary weather satellites provide images in vis- ible and infrared light. Polar-orbiting weather satel- lites survey virtually the whole Earth. Satellite instru- ments monitor stratospheric ozone concentrations, atmospheric particulates, temperature profiles as a function of atmospheric altitude, and pollutant levels (such as chlorofluorocarbons). Some measure sur- face, lower atmospheric, and ocean temperature vari- ations to monitor suspected global warming. A great advantage of global weather systems has been ad- vanced warning of hurricanes, tornadoes, and other destructive systems, resulting in tremendous savings of human life. Navigation Satellites The Global Positioning System (GPS) is a network of twenty-four Navstar satellites maintained by the U.S. Department of Defense. A person using a special re- ceiver and security codes can determine a location to fewer than 18 meters. Without those security codes, accuracy is limited to around 100 meters. This is suffi - cient for civilians to driveto a location in a strange city or to navigate a ship. The military uses GPS not only 1132 • Space resources Global Resources for navigation but also to provide flight-path correc - tions to deployed smart weapons. GPS was incorpo- rated into guidance and navigation systems aboard the space shuttle.GPS became a staple forsearch-and- rescue services and provides a means for detailed documentation of surface locations for commercial and scientific purposes. In 2009, a GPS satellite launched by a Delta II booster lifted off from Cape Canaveral. At that point, the Delta II rocket had launched forty-seven GPS sat- ellites in twenty years with only one failure. Since ini- tial GPS deployment,variousgenerations of GPS have been launched by Delta II, Atlas II, and Titan IV rock- ets. With this 2009 launch, there were thirty opera- tional satellites, well beyond the minimum of twenty- four needed for the orbital constellation. Reconnaissance, Remote Sensing, and High- Resolution Imaging Satellites In 1960, the Russians shot down an American U-2 spy plane flyingover Soviet territory.This incident under- scored the military’s desire to obtain high-resolution images in a less vulnerable manner. Soon, spy satel- lites, from the original Corona (cover name Discov- erer) reconnaissance satellites that proved the utility of military intelligence gathering from orbit to mod- ern classified electronic listening and imaging plat- forms took over from spy planes. Afterward, relying on assets from orbit became a major part of American military space programs. Resolution and other capa- bilities of military systems, naturally, remain secret. The orbital vantage point not only is useful for re- connaissance and intelligence gathering but also pro- vides a platform from which to perform Earth re- sources investigations. The story has been told of a Gulf of Mexico fisherman who, when shown an image taken from NASA’s Skylab Earth Resources Experi- ment Package (EREP), stated that he had learned more about where to find rich schools of fish and where currents and abundant nutrients flowed within his patrol area than he had during a lifetime of work- ing on thesea. Multispectral imaging could beused to conduct environmental studies as well as uncover a wide range of natural resources. From early astro- nauts using simple cameras to the Skylab EREP pack- age, theconcept ofremote sensingwas provenquickly. Public access to satellite images began in 1972 with the Landsat satellite series. A similar program to ob- serve the oceans, called Seasat, was developed with less success than Landsat. Early Landsat images had a resolution of 80 meters. During the Carter adminis- tration, NASA transferred Landsat operations to the National Oceanographic and Atmospheric Adminis- tration (NOAA). NOAA funding ran low during the first Bush administration, and NASA again entered the picture. By 1995, images with high resolution were available for commercial uses rang- ing from land management to insur- ance claims adjustment. Landsat 7 was launched in 1999. Commercial satellites followed. The IKONOS and the French Système Pour l’Observa- tion dela Terre (SPOT) systemshave resolutions closer to claimed Ameri- can military capabilities. Google Earth uses satelliteimagesto provide incredibly detailed views of Earth’s human infrastructure. As for U.S. assets, after the turn of the century, only Landsat 5 and 7 re- mained available. In August, 2007, Landsat 5unexpectedly tumbled out of its working orbit. Several days later, that satellite was recertified for con - tinued operations; some believed Landsat 5 had been hit by debris Global Resources Space resources • 1133 A rendering of an orbiting Block II-F (GPS) satellite. (NASA) from the Perseid meteor shower. This anomalous or - bit incident, however, illustrated another aspect of us- ing the resources of space: the expanding danger of micrometeoroid and orbital debris (MMOD). Both LEO and GEO have become filled with operational satellites, space junk, spent booster parts, and other debris. Quite often the International Space Station (ISS) hasto execute collision-avoidancemaneuvers to miss orbital debris. In 2009, an investigation of joint management NASA andthe Department oftheInterior U.S.Geolog- ical Survey indicated that Landsat was not meeting re- quirements of the 1992 Land Remote Sensing Policy Act. This investigation called for greater thermal im- aging capabilityand urged anexpanded Landsat Data Continuity Mission to maintain Landsat legacy data. Astronomical Satellites Atmospheric density fluctuations cause starlight to twinkle. Without adaptive optics built into land-based telescope facilities, optical images smear out and ob- scure detail. Placing the Hubble Space Telescope above the atmosphere in LEO (in 1990) enabled as- tronomers to begin resolving individual stars and dis- tant galaxiesmuch farther awaythan ever before. This provided a better measurement of the size of the ob- servable universe and a more accurate value for the rate at which the universe is expanding, the so-called Hubble constant. Other astronomical satellites have detected radiation that is partially or completely blocked by Earth’s atmosphere: infrared, ultraviolet, X-ray, and gamma-ray radiation. The Cosmic Back- ground Explorer (COBE) measured diffuse infrared and microwave radiation thought to be remnants of the big bang and revealed tiny fluctuations that may have led to galaxy formation. Vela satellites, launched in1969 to monitor theNu- clear Test Ban Treaty, discovered unexpected celestial gamma-ray emissions. The utilization of Earth-orbiting and solar-orbiting positions for astrophysical studies of the cosmos at wavelengths not available to Earth-based observatories was quickly realized by such early space- craft as the Orbiting Astronomical Observatories, the Orbiting Solar Observatories, and the High Energy As- tronomical Observatories. Theaforementioned Hub- ble Space Telescope became but one of a collectionof Great Observatories that NASA launched into space. Others were the Compton Gamma Ray Observatory, the Chandra X-Ray Observatory, and the Spitzer Space Telescope. The latter was an infrared observatory. These Great Observatories permitted coordinated studies in several ranges of the electromagnetic spec- trum, greatly expanding the understanding of high- energy astrophysics and cosmological issues. NASA and other international space agencies also developed smaller space-based observatories designed for more specific investigations. Fermi and Swift ex- tended gamma-ray studies by Compton and some Russian spacecraft. The French launched the Convec- tion Rotation and Planetary Transits (COROT) tele- scope to look for transits of extrasolar planets across their star. NASA’s Kepler spacecraft greatly exceeded COROT in capability and began looking for Earth- class planets in extrasolar systems in 2009. Manufacturing in Microgravity Any object in a circular orbit about Earth is in a state of free fall, having just enough speed (hence the right total mechanical energy) to fall around Earth instead of getting radially closer to its surface. This condition is weightlessness, a state wherein gravitational influ- ence is balanced by centripetal motion. This descrip- tion applies equally to elliptical orbits in which the or- biting object’s speed varies as it undergoes periodic orbital motion. Effects suchas the gravitational attrac- tion of other bodies on an object may give that object a weight many orders of magnitude smaller than its normal “Earth” weight, a situation referred to as “mi- crogravity.” When crystals are formed out of solution on Earth, they often develop imperfections because of convec- tive flow within the solution. More nearly perfect crys- tals can be formed in microgravity, because there are no gravitationally induced convection currents. Mi- crogravity materials processing has proven to be use- ful, but it has yet to become cost-effective. As of 2009, it cost roughly $22,000 per kilogram to deliver a pay- load to orbit. Research opportunities on the ISS in 2009 began to expand greatly under a plan to operate ISS as a na- tional laboratory with international partners. As a re- sult ofISS research,a salmonella vaccinedeveloped in space was put into clinical trials on Earth. Other phar- maceutical projects on ISS held the potential for bil- lions of dollars in profits in addition to lessening human suffering. Solar Satellite Power Stations Some have proposed using solar satellite power sta - tions (SSPS’s) to generate electrical energy. Ideas 1134 • Space resources Global Resources such as these go back as far as the late 1960’s. A large SSPS in geostationary orbit might require 50 square kilometers or more of solar collectors. Electricity from those solar collectors could be converted into micro- waves and bebeamed down to aground-based antenna array, where it could be converted into normal alter- nating electric current. In order tomaintain a safe mi- crowave beam intensity, the antenna array would need to cover many square kilometers. Some have suggested that oneor twohundred ofthese stationscould supply all electrical needs of the United States. The idea hascertain attractions,especially if the re- ceiving arrays could be situated in unpopulated re- gions. Solar power would generate no carbon dioxide emissions to aggravate global warming. On the other hand, there would be huge amounts of mining and manufacturing wastes associated with acquiringmate- rials for constructing the receiving arrays and satel- lites. Lifting the satellite materials into orbit might re- quire 30,000 to 60,000 space shuttle-class launches, which, beyond the idea’s impracticality, would be an environmental disaster in and of itself. This idea re- mains popular among certain commercial space and public space advocacy groups but has generated little government support. Mining the Moon and Mars In 1969, Gerard K. O’Neill of Princeton University set uphis freshmanphysics courseas aseminargeared toward exploring whether a planetary surface was re- ally the right place for an expanding technological civilization; the students returned a negative answer. However, consensus grew that colonies in space were feasible and could provide access to abundantenergy, raw materials, freedom, and frontiers beyond Earth. O’Neill’s disciples and successors have a remarkable idealism anda zeal abouthumankind’s placein space. They organized as the Space Studies Institute (SSI) and the Space Frontier Foundation. Other advocacy groups arose, such as the 15 Society, named after a concept to place a huge human space colony at a spe- cific Lagrange point in the Earth-Moon system. Using solar energy and appropriate industrial chemical processes, extracting oxygen, silicon, iron, calcium, aluminum, magnesium, and titanium from lunar rocks and soil should be possible. Oxygen and powdered aluminum could be used as rocket fuel. Mass drivers,devices designed withtracks andsequen - tially activated magnetic coils topropel buckets of ma - terial to launch speeds, could launch supplies from the lunar surface. Space tugs could catch these sup - plies and transport them to a space colony. It would cost much less energy to bring material from the Moon to build an SSPS than it would to provide it from Earth. Even so,it isdoubtful thatthe SSPSwould pay foritself unless the space colony were already in place. The Martian surface or perhaps Phobos, one of Mars’s two small irregular moons, could become a spacecraft fuelingstation. Water couldbe mined from polar ice or from permafrost and be converted into high-grade rocket fuel based on hydrogen and oxy- gen. Carbon dioxide from the Martian atmosphere could be processed into a rocket-fuel combination of oxygen and carbon monoxide. The ability to refuel would make access to Mars and the asteroid belt eas- ier. Aggressive exploration and exploitation of Mars have been advocated by Robert Zubrin and the Mars Society. Mars remains a long-range, albeit unfunded, goal of NASA manned spaceflight. In the aftermath of the Columbia accident in 2003, the second Bush administration advanced the Vision for Space Exploration with the motto: “The Moon, Mars, and Beyond.” The primary charge to NASA was to return to the Moon to stay, with initial lunar opera- tions to begin by 2020. A goal of steadily building up a lunar base at the Moon’s south pole, using as many in situ resources as possible, became NASA’s Project Constellation. Other nations, including China, Rus- sia, India, andJapan, developed interests inexploring lunar space as well. An implied Chinese manned spaceflight goal was to reach the Moon before NASA’s return. Apollo 17 moonwalker Harrison Schmitt de- veloped an economically sustainable plan to mine lunar soil for helium 3 to be used on Earth in fusion- based power generation systems. As of 2010, Ameri- can plansfor areturn tothe Moonwere underreview. Mining Asteroids Some asteroids are excellent sources of nickel and iron. Others contain a great deal of carbon and water. There are an estimated two thousand asteroids 1 kilo- meter in diameter or larger that cross Earth’s orbit. These asteroids are more accessible than those within the main asteroid belt. It is at least theoretically possi- ble to adjust the orbits of smaller asteroids using mass drivers or gravity tractors, but it might take years or decades to achieve thedesired orbit. It is believed that a single nickel-iron asteroid 1 kilometer in diameter would contain nearly seven times the estimated earthly nickel reserves. Global Resources Space resources • 1135 . another source of South Korean tungsten. Both mines also ex - tract molybdenum. South Korean manufacturers use Global Resources South Korea • 1127 1128 • South Korea Global Resources South Korea: Resources. naturalresources, which are protected from human appropriation. Coal South Koreangovernmentofficialsencourage extrac- tion of indigenous coal resources in an attempt to decrease imports of oil. Korean mineral resources included 2.7 billion metric tons of iron ore, 1.08 million metric tons of nickel, and 907 metric tons of gold, almost twenty-five times greater than South Korean mineral resources.

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