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Topic Review
Chemtrail Conspiracy Theory
The chemtrail conspiracy theory posits the erroneous belief that long-lasting condensation trails are "chemtrails" consisting of chemical or biological agents left in the sky by high-flying aircraft, sprayed for nefarious purposes undisclosed to the general public. Believers in this conspiracy theory say that while normal contrails dissipate relatively quickly, contrails that linger must contain additional substances. Those who subscribe to the theory speculate that the purpose of the chemical release may be solar radiation management, weather modification, psychological manipulation, human population control, biological or chemical warfare, or testing of biological or chemical agents on a population, and that the trails are causing respiratory illnesses and other health problems. The claim has been dismissed by the scientific community. There is no evidence that purported chemtrails differ from normal water-based contrails routinely left by high-flying aircraft under certain atmospheric conditions. Although proponents have tried to prove that chemical spraying occurs, their analyses have been flawed or based on misconceptions. Because of the persistence of the conspiracy theory and questions about government involvement, scientists and government agencies around the world have repeatedly explained that the supposed chemtrails are in fact normal contrails. The term chemtrail is a portmanteau of the words chemical and trail, just as contrail is a portmanteau of condensation and trail.
  • 18.5K
  • 31 Oct 2022
Topic Review
History of the Middle East
Home to the Cradle of Civilization, the Middle East (usually interchangeable with the Near East) has seen many of the world's oldest cultures and civilizations. This history started from the earliest human settlements, continuing through several major pre- and post-Islamic Empires through to the nation-states of the Middle East today. Template:Human history Egyptian civilization coalesced around 3150 BC with the political unification of Upper and Lower Egypt under the first pharaoh. Mesopotamia was home to several powerful empires that came to rule almost the entire Middle East—particularly the Assyrian Empires of 1365–1076 BC and the Neo-Assyrian Empire of 911–609 BC. From the early 7th century BC and onwards, the Iranian Medes followed by Achaemenid Persia and other subsequent Iranian states empires dominated the region. In the 1st century BC, the expanding Roman Republic absorbed the whole Eastern Mediterranean, which included much of the Near East. The Eastern Roman Empire, today commonly known as the Byzantine Empire, ruling from the Balkans to the Euphrates, became increasingly defined by and dogmatic about Christianity, gradually creating religious rifts between the doctrines dictated by the establishment in Constantinople and believers in many parts of the Middle East. From the 3rd up to the course of the 7th century AD, the entire Middle East was dominated by the Byzantines and Sassanid Persia. From the 7th century, a new power was rising in the Middle East, that of Islam. The dominance of the Arabs came to a sudden end in the mid-11th century with the arrival of the Seljuq Turks. In the early 13th century, a new wave of invaders, the armies of the Mongol Empire, mainly Turkic, swept through the region. By the early 15th century, a new power had arisen in western Anatolia, the Ottoman emirs, linguistically Turkic and religiously Islamic, who in 1453 captured the Christian Byzantine capital of Constantinople and made themselves sultans. Large parts of the Middle East became a warground between the Ottomans and Iranian Safavids for centuries starting in the early 16th century. By 1700, the Ottomans had been driven out of Hungary and the balance of power along the frontier had shifted decisively in favor of the West. The British also established effective control of the Persian Gulf, and the French extended their influence into Lebanon and Syria. In 1912, the Italians seized Libya and the Dodecanese islands, just off the coast of the Ottoman heartland of Anatolia. In the late 19th and early 20th centuries, Middle Eastern rulers tried to modernize their states to compete more effectively with the European powers. A turning point in the history of the Middle East came when oil was discovered, first in Persia in 1908 and later in Saudi Arabia (in 1938) and the other Persian Gulf states, and also in Libya and Algeria. A Western dependence on Middle Eastern oil and the decline of British influence led to a growing American interest in the region. During the 1920s, 1930s, and 1940s, Syria and Egypt made moves towards independence. The British, the French, and the Soviets departed from many parts of the Middle East during and after World War II (1939–1945). The struggle between the Arabs and the Jews in Palestine culminated in the 1947 United Nations plan to partition Palestine. Later in the midst of Cold War tensions, the Arabic-speaking countries of Western Asia and Northern Africa saw the rise of pan-Arabism. The departure of the European powers from direct control of the region, the establishment of Israel, and the increasing importance of the oil industry, marked the creation of the modern Middle East. In most Middle Eastern countries, the growth of market economies was inhibited by political restrictions, corruption and cronyism, overspending on arms and prestige projects, and over-dependence on oil revenues. The wealthiest economies in the region per capita are the small oil-rich countries of Persian Gulf: Qatar, Kuwait, Bahrain, and the United Arab Emirates. A combination of factors—among them the 1967 Six-Day War, the 1970s energy crisis beginning with the 1973 OPEC oil embargo in response to U.S. support of Israel in the Yom Kippur War, the concurrent Saudi-led popularization of Salafism/Wahhabism, and the 1978-79 Iranian Revolution—promoted the increasing rise of Islamism and the ongoing Islamic revival (Tajdid). The Fall of the Soviet Union in 1991 brought a global security refocus from the Cold War to a War on Terror. Starting in the early 2010s, a revolutionary wave popularly known as the Arab Spring brought major protests, uprisings, and revolutions to several Middle Eastern and Maghreb countries. Clashes in western Iraq on 30 December 2013 were preliminary to the Sunni pan-Islamist ISIL uprising. The term Near East can be used interchangeably with Middle East, but in a different context, especially when discussing ancient times, it may have a limited meaning, namely the northern, historically Aramaic-speaking Semitic area and adjacent Anatolian territories, marked in the two maps below.
  • 17.4K
  • 27 Oct 2022
Topic Review
Northwestern European People
Northwestern European people are a pan-ethnic group, or multi-ethnic regional grouping, and the inhabitants of Northwestern Europe. Northwest or Northwestern Europeans can usually trace back full or partial heritage to Great Britain and Ireland, Northern Germany, Denmark , Sweden, Norway , the Netherlands, Northern France, Belgium, and other places connected to Northwestern Europe geographically or culturally. As the pan-ethnic group is also a cultural category, rather than exclusively geographical; it often can include peoples with ancestry from bordering regions such as Austria, Finland , Southern Germany, and Switzerland . There is a large Northwestern European diaspora, with significant numbers within North America (Northwestern European Americans and Northwestern European Canadians), and Northwestern European Australians in Oceania. Other subgroupings of Europeans include Eastern European people and Southern European people.
  • 16.9K
  • 28 Oct 2022
Topic Review
Counterculture of the 1960s
The counterculture of the 1960s refers to an anti-establishment cultural phenomenon that developed first in the United Kingdom (UK) and the United States (US) and then spread throughout much of the Western world between the mid-1960s and the mid-1970s, with London, New York City, and San Francisco being hotbeds of early countercultural activity. The aggregate movement gained momentum as the Civil Rights Movement continued to grow, and would later become revolutionary with the expansion of the U.S. government's extensive military intervention in Vietnam. As the 1960s progressed, widespread social tensions also developed concerning other issues, and tended to flow along generational lines regarding human sexuality, women's rights, traditional modes of authority, experimentation with psychoactive drugs, and differing interpretations of the American Dream. Many key movements related to these issues were born or advanced within the counterculture of the 1960s. As the era unfolded, new cultural forms and a dynamic subculture which celebrated experimentation, modern incarnations of Bohemianism, and the rise of the hippie and other alternative lifestyles, emerged. This embracing of creativity is particularly notable in the works of British Invasion bands such as The Beatles, and filmmakers whose works became far less restricted by censorship. In addition to the trendsetting Beatles, many other creative artists, authors, and thinkers, within and across many disciplines, helped define the counterculture movement. Several factors distinguished the counterculture of the 1960s from the anti-authoritarian movements of previous eras. The post-World War II "baby boom" generated an unprecedented number of potentially disaffected young people as prospective participants in a rethinking of the direction of American and other democratic societies. Post-war affluence allowed many of the counterculture generation to move beyond a focus on the provision of the material necessities of life that had preoccupied their Depression-era parents. The era was also notable in that a significant portion of the array of behaviors and "causes" within the larger movement were quickly assimilated within mainstream society, particularly in the US, even though counterculture participants numbered in the clear minority within their respective national populations. The counterculture era essentially commenced in earnest with the assassination of John F. Kennedy in November 1963. It became absorbed into the popular culture with the termination of US combat military involvement in Southeast Asia and the end of the draft in 1973, and ultimately with the resignation of President Richard Nixon in August 1974.
  • 11.7K
  • 25 Oct 2022
Topic Review
List of Islands of Australia
This is a list of selected Australian islands grouped by State or Territory. Australia has 8,222 islands within its maritime borders.
  • 8.4K
  • 14 Oct 2022
Topic Review
Pole Shift Hypothesis
The cataclysmic pole shift fringe theory suggests that there have been geologically rapid shifts in the relative positions of the modern-day geographic locations of the poles and the axis of rotation of the Earth, creating calamities such as floods and tectonic events. There is evidence of precession and changes in axial tilt, but this change is on much longer time-scales and does not involve relative motion of the spin axis with respect to the planet. However, in what is known as true polar wander, the solid Earth can rotate with respect to a fixed spin axis. Research shows that during the last 200 million years a total true polar wander of some 30° has occurred, but that no super-rapid shifts in the Earth's pole were found during this period. A characteristic rate of true polar wander is 1° or less per million years. Between approximately 790 and 810 million years ago, when the supercontinent Rodinia existed, two geologically rapid phases of true polar wander may have occurred. In each of these, the magnetic poles of the Earth shifted by approximately 55°.
  • 8.4K
  • 10 Oct 2022
Topic Review
Bearing (Navigation)
In navigation, bearing is the horizontal angle between the direction of an object and another object, or between it and that of true north.
  • 7.5K
  • 05 Dec 2022
Topic Review
Adsorbent Technologies for Wastewater Treatment
Wastewater generation and treatment is an ever-increasing concern in the current century due to increased urbanization and industrialization. To tackle the situation of increasing environmental hazards, numerous wastewater treatment approaches are used—i.e., physical, chemical, and biological (primary to tertiary treatment) methods. Various treatment techniques being used have the risks of producing secondary pollutants. The most promising technique is the use of different materials as adsorbents that have a higher efficacy in treating wastewater, with a minimal production of secondary pollutants. Biosorption is a key process that is highly efficient and cost-effective. This method majorly uses the adsorption process/mechanism for toxicant removal from wastewater. 
  • 6.5K
  • 04 Nov 2021
Topic Review
Outer Space
Outer space, or simply space, is the expanse that exists beyond the Earth and between celestial bodies. Outer space is not completely empty—it is a hard vacuum containing a low density of particles, predominantly a plasma of hydrogen and helium, as well as electromagnetic radiation, magnetic fields, neutrinos, dust, and cosmic rays. The baseline temperature of outer space, as set by the background radiation from the Big Bang, is 2.7 kelvins (−270.45 °C; −454.81 °F). The plasma between galaxies accounts for about half of the baryonic (ordinary) matter in the universe; it has a number density of less than one hydrogen atom per cubic metre and a temperature of millions of kelvins. Local concentrations of matter have condensed into stars and galaxies. Studies indicate that 90% of the mass in most galaxies is in an unknown form, called dark matter, which interacts with other matter through gravitational but not electromagnetic forces. Observations suggest that the majority of the mass-energy in the observable universe is dark energy, a type of vacuum energy that is poorly understood. Intergalactic space takes up most of the volume of the universe, but even galaxies and star systems consist almost entirely of empty space. Outer space does not begin at a definite altitude above the Earth's surface. However, the Kármán line, an altitude of 100 km (62 mi) above sea level, is conventionally used as the start of outer space in space treaties and for aerospace records keeping. The framework for international space law was established by the Outer Space Treaty, which entered into force on 10 October 1967. This treaty precludes any claims of national sovereignty and permits all states to freely explore outer space. Despite the drafting of UN resolutions for the peaceful uses of outer space, anti-satellite weapons have been tested in Earth orbit. Humans began the physical exploration of space during the 20th century with the advent of high-altitude balloon flights. This was followed by manned rocket flights and, then, manned Earth orbit, first achieved by Yuri Gagarin of the Soviet Union in 1961. Due to the high cost of getting into space, manned spaceflight has been limited to low Earth orbit and the Moon. On the other hand, unmanned spacecraft have reached all of the known planets in the Solar System. Outer space represents a challenging environment for human exploration because of the hazards of vacuum and radiation. Microgravity also has a negative effect on human physiology that causes both muscle atrophy and bone loss. In addition to these health and environmental issues, the economic cost of putting objects, including humans, into space is very high.
  • 6.3K
  • 26 Oct 2022
Topic Review
Hot Dry Rock Geothermal Energy
Hot dry rock (HDR) is an extremely abundant source of geothermal energy that is difficult to access. A vast store of thermal energy is contained within hot – but essentially dry and impervious crystalline basement rocks found almost everywhere deep beneath Earth's surface. A concept for the extraction of useful amounts of geothermal energy from HDR originated at the Los Alamos National Laboratory in 1970, and Laboratory researchers were awarded a U.S. patent covering it. This technology has been tested extensively with multiple deep wells drilled in several field areas around world including the USA, Japan, Australia, France, and the UK and investment of billions of research funds. It continues to be the focus along with a related technique called EGS for sizable government-led research studies involving costly deep drilling and rock studies. Thermal energy has been recovered in reasonably sustainable tests over periods of years and in some cases electrical power generation was also achieved. However no commercial projects are ongoing or likely due to the high cost and limited capacity of the engineered reservoirs, associated wells, and pumping systems. Commonly tests have opened just one or more fractures such that the reservoir surface heat exchange areas are limited. For this technology to successfully compete with other energy sources, drilling costs would have to drop drastically or new approaches that result in much more extensive, complex, and higher rate flow paths through actual fracture networks would have to be established. The enthusiasim evident here on Wikipedia and in the research community is justified by the vast extent of the energy supply and the low environmental impact of the method however significant breakthroughs will be required to make this a commercial energy resource.
  • 5.8K
  • 30 Oct 2022
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