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  • 21 Aug, 2019

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Portal:Science

Science is a strict systematic discipline that builds and organizes knowledge in the form of testable hypotheses and predictions about the world. Modern science is typically divided into three major branches: the natural sciences (e.g., physics, chemistry, and biology), which study the physical world; the social sciences (e.g., economics, psychology, and sociology), which study individuals and societies; and the formal sciences (e.g., logic, mathematics, and theoretical computer science), which study formal systems, governed by axioms and rules. There is disagreement whether the formal sciences are scientific disciplines, as they do not rely on empirical evidence. Applied sciences are disciplines that use scientific knowledge for practical purposes, such as in engineering and medicine. (Full article...)

  Featured articles are displayed here, which represent some of the best content on English Wikipedia.

  • Image 2 The black-and-red broadbill (Cymbirhynchus macrorhynchos) is a species of bird in the typical broadbill family, Eurylaimidae. It is the only species in the genus Cymbirhynchus. A large, distinctive bird, it has maroon underparts, black upperparts, a maroon neck-band, and white bars on the wings. It also has a large, two-colored, blue-and-yellow bill. The species shows slight sexual dimorphism, with females being smaller than males. No other bird in its range resembles it, though the black-and-yellow broadbill has a similar call. (Full article...)

    The black-and-red broadbill (Cymbirhynchus macrorhynchos) is a species of bird in the typical broadbill family, Eurylaimidae. It is the only species in the genus Cymbirhynchus. A large, distinctive bird, it has maroon underparts, black upperparts, a maroon neck-band, and white bars on the wings. It also has a large, two-colored, blue-and-yellow bill. The species shows slight sexual dimorphism, with females being smaller than males. No other bird in its range resembles it, though the black-and-yellow broadbill has a similar call. (Full article...)
  • Image 3 Artist's conception of a protoplanetary disk There is evidence that the formation of the Solar System began about 4.6 billion years ago with the gravitational collapse of a small part of a giant molecular cloud. Most of the collapsing mass collected in the center, forming the Sun, while the rest flattened into a protoplanetary disk out of which the planets, moons, asteroids, and other small Solar System bodies formed. (Full article...)
    Artist's conception of a protoplanetary disk


    There is evidence that the formation of the Solar System began about 4.6 billion years ago with the gravitational collapse of a small part of a giant molecular cloud. Most of the collapsing mass collected in the center, forming the Sun, while the rest flattened into a protoplanetary disk out of which the planets, moons, asteroids, and other small Solar System bodies formed. (Full article...)
  • Image 4 The Qayen earthquake, also known as the Ardekul or Qaen earthquake, struck northern Iran's Khorasan Province in the vicinity of Qaen on May 10, 1997 at 07:57 UTC (12:57 local time). The largest in the area since 1990, the earthquake registered 7.3 on the moment magnitude scale and was centered approximately 270 kilometers (170 mi) south of Mashhad on the village of Ardekul. The third earthquake that year to cause severe damage, it devastated the Birjand–Qayen region, killing 1,567 and injuring more than 2,300. The earthquake—which left 50,000 homeless and damaged or destroyed over 15,000 homes—was described as the deadliest of 1997 by the United States Geological Survey. Some 155 aftershocks caused further destruction and drove away survivors. The earthquake was later discovered to have been caused by a rupture along a fault that runs underneath the Iran–Afghanistan border. (Full article...)

    The Qayen earthquake, also known as the Ardekul or Qaen earthquake, struck northern Iran's Khorasan Province in the vicinity of Qaen on May 10, 1997 at 07:57 UTC (12:57 local time). The largest in the area since 1990, the earthquake registered 7.3 on the moment magnitude scale and was centered approximately 270 kilometers (170 mi) south of Mashhad on the village of Ardekul. The third earthquake that year to cause severe damage, it devastated the Birjand–Qayen region, killing 1,567 and injuring more than 2,300. The earthquake—which left 50,000 homeless and damaged or destroyed over 15,000 homes—was described as the deadliest of 1997 by the United States Geological Survey. Some 155 aftershocks caused further destruction and drove away survivors. The earthquake was later discovered to have been caused by a rupture along a fault that runs underneath the Iran–Afghanistan border. (Full article...)
  • Image 5 Nihonium is a synthetic chemical element; it has the symbol Nh and atomic number 113. It is extremely radioactive: its most stable known isotope, nihonium-286, has a half-life of about 10 seconds. In the periodic table, nihonium is a transactinide element in the p-block. It is a member of period 7 and group 13. (Full article...)
    Nihonium is a synthetic chemical element; it has the symbol Nh and atomic number 113. It is extremely radioactive: its most stable known isotope, nihonium-286, has a half-life of about 10 seconds. In the periodic table, nihonium is a transactinide element in the p-block. It is a member of period 7 and group 13. (Full article...)
  • Image 6 Sulphur-crested Cockatoo A cockatoo is any of the 21 species of parrots belonging to the family Cacatuidae, the only family in the superfamily Cacatuoidea. Along with the Psittacoidea (true parrots) and the Strigopoidea (large New Zealand parrots), they make up the order Psittaciformes. The family has a mainly Australasian distribution, ranging from the Philippines and the eastern Indonesian islands of Wallacea to New Guinea, the Solomon Islands and Australia. (Full article...)

    A cockatoo is any of the 21 species of parrots belonging to the family Cacatuidae, the only family in the superfamily Cacatuoidea. Along with the Psittacoidea (true parrots) and the Strigopoidea (large New Zealand parrots), they make up the order Psittaciformes. The family has a mainly Australasian distribution, ranging from the Philippines and the eastern Indonesian islands of Wallacea to New Guinea, the Solomon Islands and Australia. (Full article...)
  • Image 7 Eris (center), the largest known scattered-disc object, and its moon Dysnomia (left of object) The scattered disc (or scattered disk) is a distant circumstellar disc in the Solar System that is sparsely populated by icy small Solar System bodies, which are a subset of the broader family of trans-Neptunian objects. The scattered-disc objects (SDOs) have orbital eccentricities ranging as high as 0.8, inclinations as high as 40°, and perihelia greater than 30 astronomical units (4.5×109 km; 2.8×109 mi). These extreme orbits are thought to be the result of gravitational "scattering" by the gas giants, and the objects continue to be subject to perturbation by the planet Neptune. (Full article...)
    Eris (center), the largest known scattered-disc object, and its moon Dysnomia (left of object)

    The scattered disc (or scattered disk) is a distant circumstellar disc in the Solar System that is sparsely populated by icy small Solar System bodies, which are a subset of the broader family of trans-Neptunian objects. The scattered-disc objects (SDOs) have orbital eccentricities ranging as high as 0.8, inclinations as high as 40°, and perihelia greater than 30 astronomical units (4.5×10 km; 2.8×10 mi). These extreme orbits are thought to be the result of gravitational "scattering" by the gas giants, and the objects continue to be subject to perturbation by the planet Neptune. (Full article...)
  • Image 8 Cyathus striatus Cyathus is a genus of fungi in the Nidulariaceae, which is a family collectively known as the bird's nest fungi. They are given this name as they resemble tiny bird's nests filled with "eggs" – structures large enough to have been mistaken in the past for seeds. However, these are now known to be reproductive structures containing spores. The "eggs", or peridioles, are firmly attached to the inner surface of this fruit body by an elastic cord of mycelia known as a funiculus. The 45 species are widely distributed throughout the world and some are found in most countries, although a few exist in only one or two locales. Cyathus stercoreus is considered endangered in a number of European countries. Some species of Cyathus are also known as splash cups, which refers to the fact that falling raindrops can knock the peridioles out of the open-cup fruit body. The internal and external surfaces of this cup may be ridged longitudinally (referred to as plicate or striate); this is one example of a taxonomic characteristic that has traditionally served to distinguish between species. (Full article...)

    Cyathus is a genus of fungi in the Nidulariaceae, which is a family collectively known as the bird's nest fungi. They are given this name as they resemble tiny bird's nests filled with "eggs" – structures large enough to have been mistaken in the past for seeds. However, these are now known to be reproductive structures containing spores. The "eggs", or peridioles, are firmly attached to the inner surface of this fruit body by an elastic cord of mycelia known as a funiculus. The 45 species are widely distributed throughout the world and some are found in most countries, although a few exist in only one or two locales. Cyathus stercoreus is considered endangered in a number of European countries. Some species of Cyathus are also known as splash cups, which refers to the fact that falling raindrops can knock the peridioles out of the open-cup fruit body. The internal and external surfaces of this cup may be ridged longitudinally (referred to as plicate or striate); this is one example of a taxonomic characteristic that has traditionally served to distinguish between species. (Full article...)
  • Image 9 Adult of nominate subspecies in Switzerland The Alpine chough (/ˈtʃʌf/) or yellow-billed chough (Pyrrhocorax graculus) is a bird in the crow family, one of only two species in the genus Pyrrhocorax. Its two subspecies breed in high mountains from Spain eastwards through southern Europe and North Africa to Central Asia and Nepal, and it may nest at a higher altitude than any other bird. The eggs have adaptations to the thin atmosphere that improve oxygen take-up and reduce water loss. (Full article...)

    The Alpine chough (/ˈʌf/) or yellow-billed chough (Pyrrhocorax graculus) is a bird in the crow family, one of only two species in the genus Pyrrhocorax. Its two subspecies breed in high mountains from Spain eastwards through southern Europe and North Africa to Central Asia and Nepal, and it may nest at a higher altitude than any other bird. The eggs have adaptations to the thin atmosphere that improve oxygen take-up and reduce water loss. (Full article...)
  • Image 10 Map showing nuclear test sites in Australia Between 1956 and 1963, the United Kingdom conducted seven nuclear tests at the Maralinga site in South Australia, part of the Woomera Prohibited Area about 800 kilometres (500 mi) north west of Adelaide. Two major test series were conducted: Operation Buffalo in 1956 and Operation Antler the following year. Approximate weapon yields ranged from 1 to 27 kilotons of TNT (4 to 100 TJ). The Maralinga site was also used for minor trials, tests of nuclear weapons components not involving nuclear explosions. The tests codenamed "Kittens" were trials of neutron initiators; "Rats" and "Tims" measured how the fissile core of a nuclear weapon was compressed by the high explosive shock wave; and "Vixens" investigated the effects of fire or non-nuclear explosions on atomic weapons. The minor trials, numbering around 550, ultimately generated far more contamination than the major tests. (Full article...)

    Between 1956 and 1963, the United Kingdom conducted seven nuclear tests at the Maralinga site in South Australia, part of the Woomera Prohibited Area about 800 kilometres (500 mi) north west of Adelaide. Two major test series were conducted: Operation Buffalo in 1956 and Operation Antler the following year. Approximate weapon yields ranged from 1 to 27 kilotons of TNT (4 to 100 TJ). The Maralinga site was also used for minor trials, tests of nuclear weapons components not involving nuclear explosions. The tests codenamed "Kittens" were trials of neutron initiators; "Rats" and "Tims" measured how the fissile core of a nuclear weapon was compressed by the high explosive shock wave; and "Vixens" investigated the effects of fire or non-nuclear explosions on atomic weapons. The minor trials, numbering around 550, ultimately generated far more contamination than the major tests. (Full article...)
  • Image 11 Givati Parking Lot dig The Acra (also spelled Akra, from Ancient Greek: Ἄκρα, Hebrew: חקרא ,חקרה Ḥaqra(h)), with the meaning of "stronghold" (see under "Etymology"), was a place in Jerusalem thought to have had a fortified compound built by Antiochus Epiphanes, ruler of the Seleucid Empire, following his sack of the city in 168 BCE. The name Acra was also used at a later time for a city quarter probably associated with the by-then destroyed fortress, known in his time to Josephus (1st century CE) as both Acra and "the lower city". The fortress played a significant role in the events surrounding the Maccabean Revolt, which resulted in the formation of the Hasmonean Kingdom. The "upper city" was captured by Judas Maccabeus, with the Seleucid garrison taking refuge in the "Acra" below, and the task of destroying this last enemy stronghold inside Jerusalem fell to Simon Maccabeus surnamed Thassi. Our knowledge about the Acra is based almost exclusively on the writings of Josephus, which are of a later date, and on the First and Second Books of Maccabees, which were written not long after the described events. (Full article...)

    The Acra (also spelled Akra, from Ancient Greek: Ἄκρα, Hebrew: חקרא ,חקרה Ḥaqra(h)), with the meaning of "stronghold" (see under "Etymology"), was a place in Jerusalem thought to have had a fortified compound built by Antiochus Epiphanes, ruler of the Seleucid Empire, following his sack of the city in 168 BCE. The name Acra was also used at a later time for a city quarter probably associated with the by-then destroyed fortress, known in his time to Josephus (1st century CE) as both Acra and "the lower city". The fortress played a significant role in the events surrounding the Maccabean Revolt, which resulted in the formation of the Hasmonean Kingdom. The "upper city" was captured by Judas Maccabeus, with the Seleucid garrison taking refuge in the "Acra" below, and the task of destroying this last enemy stronghold inside Jerusalem fell to Simon Maccabeus surnamed Thassi. Our knowledge about the Acra is based almost exclusively on the writings of Josephus, which are of a later date, and on the First and Second Books of Maccabees, which were written not long after the described events. (Full article...)
  • Image 12 Banksia caleyi, commonly known as Caley's banksia or red lantern banksia, is a species of woody shrub of the family Proteaceae native to Western Australia. It generally grows as a dense shrub up to 2 m (7 ft) tall, has serrated leaves and red, pendent (hanging) inflorescences which are generally hidden in the foliage. First described by Scottish naturalist Robert Brown in 1830, Banksia caleyi was named in honour of the English botanist George Caley. No subspecies are recognised. It is one of three or four related species with hanging inflorescences, which is an unusual feature within the genus. (Full article...)

    Banksia caleyi, commonly known as Caley's banksia or red lantern banksia, is a species of woody shrub of the family Proteaceae native to Western Australia. It generally grows as a dense shrub up to 2 m (7 ft) tall, has serrated leaves and red, pendent (hanging) inflorescences which are generally hidden in the foliage. First described by Scottish naturalist Robert Brown in 1830, Banksia caleyi was named in honour of the English botanist George Caley. No subspecies are recognised. It is one of three or four related species with hanging inflorescences, which is an unusual feature within the genus. (Full article...)
  • Image 13 Mounted P. transouralicum skeleton, Moscow Paleontological Museum; this is the most completely known skeleton, but the skull is a cast of a specimen at American Museum of Natural History Paraceratherium is an extinct genus of hornless rhinocerotoids belonging to the family Paraceratheriidae. It is one of the largest terrestrial mammals that has ever existed and lived from the early to late Oligocene epoch (34–23 million years ago). The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. Paraceratherium means "near the hornless beast", in reference to Aceratherium, the genus in which the type species P. bugtiense was originally placed. (Full article...)

    Paraceratherium is an extinct genus of hornless rhinocerotoids belonging to the family Paraceratheriidae. It is one of the largest terrestrial mammals that has ever existed and lived from the early to late Oligocene epoch (34–23 million years ago). The first fossils were discovered in what is now Pakistan, and remains have been found across Eurasia between China and the Balkans. Paraceratherium means "near the hornless beast", in reference to Aceratherium, the genus in which the type species P. bugtiense was originally placed. (Full article...)
  • Image 14 Coccinella septempunctata Coccinellidae (/ˌkɒksɪˈnɛlɪdiː/) is a widespread family of small beetles. They are commonly known as ladybugs in North America and ladybirds in the United Kingdom; "lady" refers to mother Mary. Entomologists use the names ladybird beetles or lady beetles to avoid confusion with true bugs. The more than 6,000 described species have a global distribution and are found in a variety of habitats. They are oval beetles with a domed back and flat underside. Many of the species have conspicuous aposematic (warning) colours and patterns, such as red with black spots, that warn potential predators that they taste bad. (Full article...)

    Coccinellidae (/ˌkɒksɪˈnɛlɪd/) is a widespread family of small beetles. They are commonly known as ladybugs in North America and ladybirds in the United Kingdom; "lady" refers to mother Mary. Entomologists use the names ladybird beetles or lady beetles to avoid confusion with true bugs. The more than 6,000 described species have a global distribution and are found in a variety of habitats. They are oval beetles with a domed back and flat underside. Many of the species have conspicuous aposematic (warning) colours and patterns, such as red with black spots, that warn potential predators that they taste bad. (Full article...)
  • Image 15 The visitor centre, formerly a lifeboat station Blakeney Point (designated as Blakeney National Nature Reserve) is a national nature reserve situated near to the villages of Blakeney, Morston and Cley next the Sea on the north coast of Norfolk, England. Its main feature is a 6.4 km (4.0 mi) spit of shingle and sand dunes, but the reserve also includes salt marshes, tidal mudflats and reclaimed farmland. It has been managed by the National Trust since 1912, and lies within the North Norfolk Coast Site of Special Scientific Interest, which is additionally protected through Natura 2000, Special Protection Area (SPA), International Union for Conservation of Nature (IUCN) and Ramsar listings. The reserve is part of both an Area of Outstanding Natural Beauty (AONB), and a World Biosphere Reserve. The Point has been studied for more than a century, following pioneering ecological studies by botanist Francis Wall Oliver and a bird ringing programme initiated by ornithologist Emma Turner. (Full article...)

    Blakeney Point (designated as Blakeney National Nature Reserve) is a national nature reserve situated near to the villages of Blakeney, Morston and Cley next the Sea on the north coast of Norfolk, England. Its main feature is a 6.4 km (4.0 mi) spit of shingle and sand dunes, but the reserve also includes salt marshes, tidal mudflats and reclaimed farmland. It has been managed by the National Trust since 1912, and lies within the North Norfolk Coast Site of Special Scientific Interest, which is additionally protected through Natura 2000, Special Protection Area (SPA), International Union for Conservation of Nature (IUCN) and Ramsar listings. The reserve is part of both an Area of Outstanding Natural Beauty (AONB), and a World Biosphere Reserve. The Point has been studied for more than a century, following pioneering ecological studies by botanist Francis Wall Oliver and a bird ringing programme initiated by ornithologist Emma Turner. (Full article...)
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    A society (/səˈsəti/) is a group of individuals involved in persistent social interaction or a large social group sharing the same spatial or social territory, typically subject to the same political authority and dominant cultural expectations. Societies are characterized by patterns of relationships (social relations) between individuals who share a distinctive culture and institutions; a given society may be described as the sum total of such relationships among its constituent members. (Full article...)
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    Science News

    24 July 2024 –
    Researchers from the Scottish Association for Marine Science report evidence of dark oxygen being produced from metals on the seafloor. It was previously assumed that almost all the free oxygen (O
    2
    ) on Earth was created through photosynthesis, which requires sunlight. (NPR)
    23 July 2024 –
    A study by the Oswaldo Cruz Foundation finds thirteen Brazilian sharpnose sharks off the coast of Brazil with high levels of cocaine in their muscles and livers. Experts believe that the cocaine is making its way into the waters via illegal labs where the drug is manufactured or through the excrement of drug users. (BBC News)
    15 July 2024 – Mare Tranquillitatis pit
    In the journal Nature Astronomy, American and Italian scientists announce the discovery of a lunar cave, approximately 250 miles (400 km) from the landing site of Apollo 11. (AP) (Nature Astronomy)
    10 July 2024 –
    Researchers from Northwestern University Feinberg School of Medicine and Harvard Medical School publish a claim for the cause and curative path for the autoimmune disease systemic lupus erythematosus in the journal Nature. (Newsmax) (Nature)
    3 July 2024 –
    Scientists announce the discovery of the world's oldest cave painting, depicting three people gathered around a large red pig, estimated to be at least 51,200 years old, in Leang Karampurang cave in the Maros-Pangkep region, South Sulawesi, Indonesia. (Al Jazeera)
    20 June 2024 – 2024 in archosaur paleontology
    Researchers announce the discovery the Lokiceratops rangiformis, a dinosaur species named after the Norse god Loki, in North America. The findings are published in the journal PeerJ. (ABC News)
    This following Science-related articles is a most visited articles of WikiProject Science, See complete list at Wikipedia:WikiProject Science/Popular pages.

  • Image 2 Artificial intelligence (AI), in its broadest sense, is intelligence exhibited by machines, particularly computer systems. It is a field of research in computer science that develops and studies methods and software that enable machines to perceive their environment and use learning and intelligence to take actions that maximize their chances of achieving defined goals. Such machines may be called AIs. (Full article...)
    Artificial intelligence (AI), in its broadest sense, is intelligence exhibited by machines, particularly computer systems. It is a field of research in computer science that develops and studies methods and software that enable machines to perceive their environment and use learning and intelligence to take actions that maximize their chances of achieving defined goals. Such machines may be called AIs. (Full article...)
  • Image 3 Science is a strict systematic discipline that builds and organizes knowledge in the form of testable hypotheses and predictions about the world. Modern science is typically divided into three major branches: the natural sciences (e.g., physics, chemistry, and biology), which study the physical world; the social sciences (e.g., economics, psychology, and sociology), which study individuals and societies; and the formal sciences (e.g., logic, mathematics, and theoretical computer science), which study formal systems, governed by axioms and rules. There is disagreement whether the formal sciences are scientific disciplines, as they do not rely on empirical evidence. Applied sciences are disciplines that use scientific knowledge for practical purposes, such as in engineering and medicine. (Full article...)
    Science is a strict systematic discipline that builds and organizes knowledge in the form of testable hypotheses and predictions about the world. Modern science is typically divided into three major branches: the natural sciences (e.g., physics, chemistry, and biology), which study the physical world; the social sciences (e.g., economics, psychology, and sociology), which study individuals and societies; and the formal sciences (e.g., logic, mathematics, and theoretical computer science), which study formal systems, governed by axioms and rules. There is disagreement whether the formal sciences are scientific disciplines, as they do not rely on empirical evidence. Applied sciences are disciplines that use scientific knowledge for practical purposes, such as in engineering and medicine. (Full article...)
  • Image 4 File:Ejaculation educational seq 4.png Example of an ejaculation Ejaculation is the discharge of semen (the ejaculate; normally containing sperm) through the urethra in men. It is normally linked with orgasm, which involves involuntary contractions of the pelvic floor. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. Ejaculation can occur spontaneously during sleep, and is a normal part of human sexual development (a nocturnal emission or "wet dream"). In rare cases, ejaculation occurs because of prostatic disease. Anejaculation is the condition of being unable to ejaculate. Ejaculation is normally intensely pleasurable for men; dysejaculation is an ejaculation that is painful or uncomfortable. Retrograde ejaculation is the backward flow of semen into the bladder rather than out of the urethra. (Full article...)

    Ejaculation is the discharge of semen (the ejaculate; normally containing sperm) through the urethra in men. It is normally linked with orgasm, which involves involuntary contractions of the pelvic floor. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. Ejaculation can occur spontaneously during sleep, and is a normal part of human sexual development (a nocturnal emission or "wet dream"). In rare cases, ejaculation occurs because of prostatic disease. Anejaculation is the condition of being unable to ejaculate. Ejaculation is normally intensely pleasurable for men; dysejaculation is an ejaculation that is painful or uncomfortable. Retrograde ejaculation is the backward flow of semen into the bladder rather than out of the urethra. (Full article...)
  • Image 5 A plot of normal distribution (or bell-shaped curve) where each band has a width of 1 standard deviation – See also: 68–95–99.7 rule. In statistics, the standard deviation is a measure of the amount of variation of a random variable expected about its mean. A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the values are spread out over a wider range. The standard deviation is commonly used in the determination of what constitutes an outlier and what does not. (Full article...)
    A plot of normal distribution (or bell-shaped curve) where each band has a width of 1 standard deviation – See also: 68–95–99.7 rule.

    In statistics, the standard deviation is a measure of the amount of variation of a random variable expected about its mean. A low standard deviation indicates that the values tend to be close to the mean (also called the expected value) of the set, while a high standard deviation indicates that the values are spread out over a wider range. The standard deviation is commonly used in the determination of what constitutes an outlier and what does not. (Full article...)
  • Image 6 An error (from the Latin errāre, meaning 'to wander') is an inaccurate or incorrect action, thought, or judgement. (Full article...)
    An error (from the Latin errāre, meaning 'to wander') is an inaccurate or incorrect action, thought, or judgement. (Full article...)
  • Image 7 The eight planets of the Solar System with size to scale (up to down, left to right): Saturn, Jupiter, Uranus, Neptune (outer planets), Earth, Venus, Mars, and Mercury (inner planets) A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets by the most restrictive definition of the term: the terrestrial planets Mercury, Venus, Earth, and Mars, and the giant planets Jupiter, Saturn, Uranus, and Neptune. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion. (Full article...)
    The eight planets of the Solar System with size to scale (up to down, left to right): Saturn, Jupiter, Uranus, Neptune (outer planets), Earth, Venus, Mars, and Mercury (inner planets)

    A planet is a large, rounded astronomical body that is generally required to be in orbit around a star, stellar remnant, or brown dwarf, and is not one itself. The Solar System has eight planets by the most restrictive definition of the term: the terrestrial planets Mercury, Venus, Earth, and Mars, and the giant planets Jupiter, Saturn, Uranus, and Neptune. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a young protostar orbited by a protoplanetary disk. Planets grow in this disk by the gradual accumulation of material driven by gravity, a process called accretion. (Full article...)
  • Image 8 Sci-Hub is a shadow library website that provides free access to millions of research papers, regardless of copyright, by bypassing publishers' paywalls in various ways. Unlike Library Genesis, it does not provide access to books. Sci-Hub was founded in Kazakhstan by Alexandra Elbakyan in 2011, in response to the high cost of research papers behind paywalls (see Serials crisis). The site is extensively used worldwide. In September 2019, the site's operator(s) said that it served approximately 400,000 requests per day. In addition to its intensive use, Sci-Hub stands out among other shadow libraries because of its easy use/reliability and because of the enormous size of its collection; a 2018 study estimated that Sci-Hub provided access to 95% of all scholarly publications with issued DOI numbers, and on 15 July 2022, Sci-Hub reported that its collection comprised 88,343,822 files. However, due to legal troubles (see legal section) the site has paused uploads. (Full article...)
    Sci-Hub is a shadow library website that provides free access to millions of research papers, regardless of copyright, by bypassing publishers' paywalls in various ways. Unlike Library Genesis, it does not provide access to books. Sci-Hub was founded in Kazakhstan by Alexandra Elbakyan in 2011, in response to the high cost of research papers behind paywalls (see Serials crisis). The site is extensively used worldwide. In September 2019, the site's operator(s) said that it served approximately 400,000 requests per day.
    In addition to its intensive use, Sci-Hub stands out among other shadow libraries because of its easy use/reliability and because of the enormous size of its collection; a 2018 study estimated that Sci-Hub provided access to 95% of all scholarly publications with issued DOI numbers, and on 15 July 2022, Sci-Hub reported that its collection comprised 88,343,822 files. However, due to legal troubles (see legal section) the site has paused uploads. (Full article...)
  • Image 9 In this illustration by Milo Winter of Aesop's fable, "The North Wind and the Sun", a personified North Wind tries to strip the cloak off a traveler. Anthropomorphism is the attribution of human traits, emotions, or intentions to non-human entities. It is considered to be an innate tendency of human psychology. Personification is the related attribution of human form and characteristics to abstract concepts such as nations, emotions, and natural forces, such as seasons and weather. Both have ancient roots as storytelling and artistic devices, and most cultures have traditional fables with anthropomorphized animals as characters. People have also routinely attributed human emotions and behavioral traits to wild as well as domesticated animals. (Full article...)
    In this illustration by Milo Winter of Aesop's fable, "The North Wind and the Sun", a personified North Wind tries to strip the cloak off a traveler.

    Anthropomorphism is the attribution of human traits, emotions, or intentions to non-human entities. It is considered to be an innate tendency of human psychology. Personification is the related attribution of human form and characteristics to abstract concepts such as nations, emotions, and natural forces, such as seasons and weather. Both have ancient roots as storytelling and artistic devices, and most cultures have traditional fables with anthropomorphized animals as characters. People have also routinely attributed human emotions and behavioral traits to wild as well as domesticated animals. (Full article...)
  • Image 10 The expansion of the universe according to the Big Bang theory in physics Physics is the natural science of matter, involving the study of matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. Physics is one of the most fundamental scientific disciplines. A scientist who specializes in the field of physics is called a physicist. (Full article...)
    The expansion of the universe according to the Big Bang theory in physics

    Physics is the natural science of matter, involving the study of matter, its fundamental constituents, its motion and behavior through space and time, and the related entities of energy and force. Physics is one of the most fundamental scientific disciplines. A scientist who specializes in the field of physics is called a physicist. (Full article...)
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