Portal:Science
Jump to navigation
Jump to search
| Main page | Categories & Main topics | Related portals & WikiProjects | Things you can do |
Science portal
Science (from the Latin word scientia, meaning "knowledge") is a systematic enterprise that builds and organizes knowledge in the form of testable explanations and predictions about the universe.
The earliest roots of science can be traced to Ancient Egypt and Mesopotamia in around 3000 to 1200 BCE. Their contributions to mathematics, astronomy, and medicine entered and shaped Greek natural philosophy of classical antiquity, whereby formal attempts were made to provide explanations of events in the physical world based on natural causes. After the fall of the Western Roman Empire, knowledge of Greek conceptions of the world deteriorated in Western Europe during the early centuries (400 to 1000 CE) of the Middle Ages, but was preserved in the Muslim world during the Islamic Golden Age. The recovery and assimilation of Greek works and Islamic inquiries into Western Europe from the 10th to 13th century revived "natural philosophy", which was later transformed by the Scientific Revolution that began in the 16th century as new ideas and discoveries departed from previous Greek conceptions and traditions. The scientific method soon played a greater role in knowledge creation and it was not until the 19th century that many of the institutional and professional features of science began to take shape; along with the changing of "natural philosophy" to "natural science."
Modern science is typically divided into three major branches that consist of the natural sciences (e.g., biology, chemistry, and physics), which study nature in the broadest sense; 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 abstract concepts. There is disagreement, however, on whether the formal sciences actually constitute a science as they do not rely on empirical evidence. Disciplines that use existing scientific knowledge for practical purposes, such as engineering and medicine, are described as applied sciences.
Science is based on research, which is commonly conducted by scientists working in academic and research institutions, government agencies, and companies. The practical impact of scientific research has led to the emergence of science policies that seek to influence the scientific enterprise by prioritizing the development of commercial products, armaments, health care, public infrastructure, and environmental protection. (Full article...)
Selected article
Subfossil lemurs are lemurs from Madagascar that are represented by recent (subfossil) remains dating from nearly 26,000 years ago to approximately 560 years ago (from the late Pleistocene until the Holocene). They include both extant and extinct species, although the term more frequently refers to the extinct giant lemurs. The diversity of subfossil lemur communities was greater than that of present-day lemur communities, ranging from as high as 20 or more species per location, compared with 10 to 12 species today. Extinct species are estimated to have ranged in size from slightly over 10 kg (22 lb) to roughly 160 kg (350 lb). Even the subfossil remains of living species are larger and more robust than the skeletal remains of modern specimens. The subfossil sites found around most of the island demonstrate that most giant lemurs had wide distributions and that ranges of living species have contracted significantly since the arrival of humans.
Despite their size, the giant lemurs shared many features with living lemurs, including rapid development, poor day vision, relatively small brains, and female-dominated hierarchies. They also had many distinct traits among lemurs, including a tendency to rely on terrestrial locomotion, slow climbing, and suspension instead of leaping, as well as a greater dependence on leaf-eating and seed predation. The giant lemurs likely filled ecological niches now left vacant, particularly seed dispersal for plants with large seeds. There were three distinct families of giant lemur, including the Palaeopropithecidae (sloth lemurs), Megaladapidae (koala lemurs), and Archaeolemuridae (monkey lemurs). Two other types were more closely related and similar in appearance to living lemurs: the giant aye-aye and Pachylemur, a genus of "giant ruffed lemurs". (Full article...)
Mycena haematopus, commonly known as the bleeding fairy helmet, the burgundydrop bonnet, or the bleeding Mycena, is a species of fungus in the family Mycenaceae, of the order Agaricales. It is widespread and common in Europe and North America, and has also been collected in Japan and Venezuela. It is saprotrophic—meaning that it obtains nutrients by consuming decomposing organic matter—and the fruit bodies appear in small groups or clusters on the decaying logs, trunks, and stumps of deciduous trees, particularly beech. The fungus, first described scientifically in 1799, is classified in the section Lactipedes of the genus Mycena, along with other species that produce a milky or colored latex.
The fruit bodies of M. haematopus have caps that are up to 4 cm (1.6 in) wide, whitish gills, and a thin, fragile reddish-brown stem with thick coarse hairs at the base. They are characterized by their reddish color, the scalloped cap edges, and the dark red latex they "bleed" when cut or broken. Both the fruit bodies and the mycelia are weakly bioluminescent. M. haematopus produces various alkaloid pigments unique to this species. The edibility of the fruit bodies is not known definitively. (Full article...)
James Emory "Jim" Boyd (July 18, 1906 – February 18, 1998) was an American physicist, mathematician, and academic administrator. He was director of the Georgia Tech Research Institute from 1957 to 1961, president of West Georgia College (now the University of West Georgia) from 1961 to 1971, and acting president of the Georgia Institute of Technology from 1971 to 1972.
A graduate of the University of Georgia, Duke University, and Yale University, Boyd began in academia as an instructor of physics at the University of Georgia, then head of the Mathematics and Science Department at West Georgia College. Subsequently, he became a professor at Georgia Tech and a prominent researcher at the Engineering Experiment Station, now known as the Georgia Tech Research Institute. At the Engineering Experiment Station, Boyd helped spur the organization's mainstay: federally funded electronics research and development. Along with fellow Georgia Tech researchers Gerald Rosselot and Glen P. Robinson, Boyd was influential in the founding of Scientific Atlanta, where he was a board member for 25 years. As director of the Engineering Experiment Station, Boyd focused on the recruitment of talented engineers and an increase in physical space available to the organization, including the establishment of nuclear research at Georgia Tech with a radioisotopes laboratory and the construction of the Frank H. Neely Research Reactor. (Full article...)
The MAUD Committee was a British scientific working group formed during the Second World War. It was established to perform the research required to determine if an atomic bomb was feasible. The name MAUD came from a strange line in a telegram from Danish physicist Niels Bohr referring to his housekeeper, Maud Ray.
The MAUD Committee was founded in response to the Frisch-Peierls memorandum, which was written in March 1940 by Rudolf Peierls and Otto Frisch, two physicists who were refugees from Nazi Germany working at the University of Birmingham under the direction of Mark Oliphant. The memorandum argued that a small sphere of pure uranium-235 could have the explosive power of thousands of tons of TNT. (Full article...)
The elfin woods warbler (Setophaga angelae) is a species of bird endemic to Puerto Rico, where it is local and uncommon. Discovered in 1968 and described in 1972, it is the most recently described New World warbler (family Parulidae).
The species name, angelae, is a tribute to Angela Kepler, one of its discoverers. The species birds are insectivores, as they feed by gleaning small insects off the habitat leaves. (Full article...)
The red-backed fairywren (Malurus melanocephalus) is a species of passerine bird in the Australasian wren family, Maluridae. It is endemic to Australia and can be found near rivers and coastal areas along the northern and eastern coastlines from the Kimberley in the northwest to the Hunter Region in New South Wales. The male adopts a striking breeding plumage, with a black head, upperparts and tail, and a brightly coloured red back and brown wings. The female has brownish upperparts and paler underparts. The male in eclipse plumage and the juvenile resemble the female. Some males remain in non-breeding plumage while breeding. Two subspecies are recognised; the nominate M. m. melanocephalus of eastern Australia has a longer tail and orange back, and the short-tailed M. m. cruentatus from northern Australia has a redder back.
The red-backed fairywren mainly eats insects, and supplements its diet with seed and small fruit. The preferred habitat is heathland and savannah, particularly where low shrubs and tall grasses provide cover. It can be nomadic in areas where there are frequent bushfires, although pairs or small groups of birds maintain and defend territories year-round in other parts of its range. Groups consist of a socially monogamous pair with one or more helper birds who assist in raising the young. These helpers are progeny that have attained sexual maturity yet remain with the family group for one or more years after fledging. The red-backed fairywren is sexually promiscuous, and each partner may mate with other individuals and even assist in raising the young from such pairings. Older males in breeding plumage are more likely to engage in this behaviour than are those breeding in eclipse plumage. As part of a courtship display, the male wren plucks red petals from flowers and displays them to females. (Full article...)
Adult male S. c. carolinensis in Algonquin Provincial Park, Canada
The white-breasted nuthatch (Sitta carolinensis) is a small songbird of the nuthatch family common across much of temperate North America. It is stocky, with a large head, short tail, powerful bill, and strong feet. It has a black cap, white face, chest, and flanks, blue-gray upperparts, and a chestnut lower belly. Its nine subspecies differ mainly in the color of the body plumage.
Like other nuthatches, the white-breasted nuthatch forages for insects on trunks and branches and is able to move head-first down trees. Seeds form a substantial part of its winter diet, as do acorns and hickory nuts stored in the fall. Old-growth woodland is preferred for breeding. The nest is in a hole in a tree, and the breeding pair may smear insects around the entrance as a deterrent to squirrels. Predators include hawks, owls, and snakes. Forest clearance may lead to local habitat loss, but there are no major conservation concerns over most of its range. (Full article...)- Caesium (IUPAC spelling) (also spelled cesium in American English) is a chemical element with the symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of 28.5 °C (83.3 °F), which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium has physical and chemical properties similar to those of rubidium and potassium. The most reactive of all metals, it is pyrophoric and reacts with water even at −116 °C (−177 °F). It is the least electronegative element, with a value of 0.79 on the Pauling scale. It has only one stable isotope, caesium-133. Caesium is mined mostly from pollucite, while the radioisotopes, especially caesium-137, a fission product, are extracted from waste produced by nuclear reactors.
The German chemist Robert Bunsen and physicist Gustav Kirchhoff discovered caesium in 1860 by the newly developed method of flame spectroscopy. The first small-scale applications for caesium were as a "getter" in vacuum tubes and in photoelectric cells. In 1967, acting on Einstein's proof that the speed of light is the most constant dimension in the universe, the International System of Units used two specific wave counts from an emission spectrum of caesium-133 to co-define the second and the metre. Since then, caesium has been widely used in highly accurate atomic clocks. (Full article...)
Suillus luteus is a bolete fungus, and the type species of the genus Suillus. A common fungus native to Eurasia, from the British Isles to Korea, it has been introduced widely elsewhere, including North and South America, southern Africa, Australia and New Zealand. Commonly referred to as slippery jack or sticky bun in English-speaking countries, its names refer to the brown cap, which is characteristically slimy in wet conditions. The fungus, initially described as Boletus luteus by Carl Linnaeus in 1753, is now classified in a different family as well as genus. Suillus luteus is edible, though not as highly regarded as other bolete mushrooms, and is commonly prepared and eaten in soups, stews or fried dishes. The slime coating, however, may cause indigestion if not removed before eating.
The fungus grows in coniferous forests in its native range, and pine plantations in countries where it has become naturalized. It forms symbiotic ectomycorrhizal associations with living trees by enveloping the tree's underground roots with sheaths of fungal tissue. The fungus produces spore-bearing fruit bodies, often in large numbers, above ground in summer and autumn. The fruit body cap often has a distinctive conical shape before flattening with age, reaching up to 13 cm (5 in) in diameter. Like other boletes, it has tubes extending downward from the underside of the cap, rather than gills; spores escape at maturity through the tube openings, or pores. The pore surface is yellow, and covered by a membranous partial veil when young. The pale stipe, or stem, measures up to 10 cm (4 in) tall and 3 cm (1.2 in) thick and bears small dots near the top. Unlike most other boletes, it bears a distinctive membranous ring that is tinged brown to violet on the underside. (Full article...)
The 2005 Azores subtropical storm was the 19th nameable storm and only subtropical storm of the extremely active 2005 Atlantic hurricane season. It was not officially named by the US National Hurricane Center as it was operationally classified as a non-tropical low. The storm developed in the eastern Atlantic Ocean out of a low-pressure area that gained subtropical characteristics on October 4. The storm was short-lived, crossing over the Azores later on October 4 before becoming extratropical again on October 5. No damages or fatalities were reported during that time. After being absorbed into a cold front, the system went on to become Hurricane Vince, which affected the Iberian Peninsula.
Months after the hurricane season, when the National Hurricane Center was performing its annual review of the season and its named storms, forecasters Jack Beven and Eric Blake identified this previously unnoticed subtropical storm. Despite its unusual location and wide wind field, the system had a well-defined centre convecting around a warm core. (Full article...)
Meinhard Michael Moser (13 March 1924 – 30 September 2002) was an Austrian mycologist. His work principally concerned the taxonomy, chemistry, and toxicity of the gilled mushrooms (Agaricales), especially those of the genus Cortinarius, and the ecology of ectomycorrhizal relationships. His contributions to the Kleine Kryptogamenflora von Mitteleuropa series of mycological guidebooks were well regarded and widely used. In particular, his 1953 Blätter- und Bauchpilze (Agaricales und Gastromycetes) [The Gilled and Gasteroid Fungi (Agaricales and Gastromycetes)], which became known as simply "Moser", saw several editions in both the original German and in translation. Other important works included a 1960 monograph on the genus Phlegmacium (now considered part of Cortinarius) and a 1975 study of members of Cortinarius, Dermocybe, and Stephanopus in South America, co-authored with the mycologist Egon Horak.
After showing interest in natural sciences in his youth, Moser studied at the University of Innsbruck. His university career began during World War II however, and was soon interrupted by military service. Stationed as a translator in eastern Europe, he was captured and placed in a prisoner-of-war camp. He was released in 1948, subsequently returning to Innsbruck to complete his studies. After completing his doctorate in 1950, Moser worked in England for six months, researching the symbiotic relationships between plants and fungi. Upon his return to Austria, he joined the Federal Forestry Research Institute, where he remained until 1968, conducting influential research on the use of mycorrhizal fungi in reforestation. He began lecturing at the University of Innsbruck in 1956, and in 1972 became the inaugural head of the first Institute of Microbiology in Austria. He remained with the Institute until his retirement in 1991, and his scientific studies continued until his death in 2002. An influential mycologist who described around 500 new taxa, Moser received awards throughout his life, and numerous fungal taxa have been named in his honour. (Full article...)
The eastern side of the monument, showing the surviving stone burial chamber at the top of the slope and fallen sarsens at the bottom
The Coldrum Long Barrow, also known as the Coldrum Stones and the Adscombe Stones, is a chambered long barrow located near the village of Trottiscliffe in the south-eastern English county of Kent. Probably constructed in the fourth millennium BCE, during Britain's Early Neolithic period, today it survives only in a state of ruin.
Archaeologists have established that the monument was built by pastoralist communities shortly after the introduction of agriculture to Britain from continental Europe. Part of an architectural tradition of long barrow building that was widespread across Neolithic Europe, the Coldrum Stones belong to a localised regional variant of barrows produced in the vicinity of the River Medway, now known as the Medway Megaliths. Of these, it is in the best surviving condition. It lies near to both Addington Long Barrow and Chestnuts Long Barrow on the western side of the river. Two further surviving long barrows, Kit's Coty House and Little Kit's Coty House, as well as possible survivals such as the Coffin Stone and White Horse Stone, are located on the Medway's eastern side. (Full article...)
Borobudur, a UNESCO World Heritage Site
Borobudur, also transcribed Barabudur (Indonesian: Candi Borobudur, Javanese: ꦕꦤ꧀ꦝꦶꦧꦫꦧꦸꦝꦸꦂ, romanized: Candhi Barabudhur) is a 7th-century Mahayana Buddhist temple in Magelang Regency, not far from the town of Muntilan, in Central Java, Indonesia. It is the world's largest Buddhist temple. The temple consists of nine stacked platforms, six square and three circular, topped by a central dome. It is decorated with 2,672 relief panels and 504 Buddha statues. The central dome is surrounded by 72 Buddha statues, each seated inside a perforated stupa.
Built in the 7th century during the reign of the Sailendra Dynasty, the temple design follows Javanese Buddhist architecture, which blends the Indonesian indigenous cult of ancestor worship and the Buddhist concept of attaining Nirvana. The temple demonstrates the influences of Gupta art that reflects India's influence on the region, yet there are enough indigenous scenes and elements incorporated to make Borobudur uniquely Indonesian. The monument is a shrine to the Buddha and a place for Buddhist pilgrimage. The pilgrim journey begins at the base of the monument and follows a path around the monument, ascending to the top through three levels symbolic of Buddhist cosmology: Kāmadhātu (the world of desire), Rūpadhātu (the world of forms) and Arūpadhātu (the world of formlessness). The monument guides pilgrims through an extensive system of stairways and corridors with 1,460 narrative relief panels on the walls and the balustrades. Borobudur has one of the largest and most complete ensembles of Buddhist reliefs in the world. (Full article...)
Cast of the holotype tooth (DK 315), Geological Museum, Copenhagen
Dromaeosauroides is a genus of dromaeosaurid theropod dinosaur from the Early Cretaceous of what is now Denmark. It was discovered in the Jydegaard Formation in the Robbedale valley, on the island of Bornholm in the Baltic Sea. This is the only likely place for dinosaur remains to be discovered on Danish territory, since the Mesozoic deposits exposed in the rest of the country are marine. Dromaeosauroides is the first known dinosaur from this location, and the only one which has been scientifically named. It is one of the oldest known dromaeosaurs in the world, and the first known uncontested dromaeosaur from the Early Cretaceous of Europe.
It is known from two teeth, the first of which was found in 2000 and the second in 2008. Based on the first tooth (the holotype), the genus and species Dromaeosauroides bornholmensis was named in 2003. The genus name means "Dromaeosaurus-like", due to the similarity to the teeth of that genus, and the species name means "from Bornholm". After this discovery, remains and tracks of more dinosaurs were found in several formations on Bornholm. Some teeth from the United Kingdom that have been referred to the genus Nuthetes may also belong to this animal. Coprolites containing fish remains found in the Jydegaard Formation may belong to Dromaeosauroides. (Full article...)
Mounted V. mongoliensis cast at Dinosaur Journey Museum
Velociraptor (/vɪˈlɒsɪræptər/; meaning "swift seizer" in Latin) is a genus of dromaeosaurid theropod dinosaur that lived approximately 75 to 71 million years ago during the latter part of the Cretaceous Period. Two species are currently recognized, although others have been assigned in the past. The type species is V. mongoliensis; fossils of this species have been discovered in Mongolia. A second species, V. osmolskae, was named in 2008 for skull material from Inner Mongolia, China.
Smaller than other dromaeosaurids like Deinonychus and Achillobator, Velociraptor nevertheless shared many of the same anatomical features. It was a bipedal, feathered carnivore with a long tail and an enlarged sickle-shaped claw on each hindfoot, which is thought to have been used to tackle and disembowel prey. Velociraptor can be distinguished from other dromaeosaurids by its long and low skull, with an upturned snout. (Full article...)
Selected image
The Milky Way is a barred spiral galaxy of the Local Group. Although the Milky Way is but one of billions of galaxies in the universe, the Galaxy has special significance to humanity as it is the home of the Solar System. The term "milky" originates from the hazy band of white light appearing across the celestial sphere visible from Earth, which is composed of stars and other material lying within the galactic plane. The fact that the Milky Way divides the night sky into two roughly equal hemispheres indicates that the solar system lies close to the galactic plane.
Selected biography
Francis Crick, Francis Harry Compton Crick OM FRS (8 June 1916 – 28 July 2004), was a British molecular biologist, physicist, and neuroscientist, and most noted for being one of the co-discoverers of the structure of the DNA molecule in 1953. He, James D. Watson and Maurice Wilkins were jointly awarded the 1962 Nobel Prize for Physiology or Medicine "for their discoveries concerning the molecular structure of nucleic acids and its significance for information transfer in living material" .[2]
Did you know...
- ...that coloration is a property of loudspeakers that causes the speaker to continue to emit sound when an electrical signal stops?
- ...that light in a plasma display is created by phosphors excited by the ultraviolet radiation emitted by a plasma discharge between two flat panels of glass?
- ...that the Great Appalachian Storm of November 1950 led to wind gusts in excess of 100 mph/87 knots across New York, New Jersey, and New England?
- ...that the two human atria do not have valves at their inlets?
Science News
- 24 February 2021 –
- Scientists discover Dzharatitanis kingi, a Diplodocus-like dinosaur fossil, in Uzbekistan. It is the first dinosaur of its kind to be discovered in Asia. (New Scientist)
- 17 February 2021 – Discoveries of exoplanets
- Astronomers announce the discovery of HD 110082 b, a sub-Neptune exoplanet that is three times larger than Earth and which orbits a relatively young star. (Phys.org)
- 5 February 2021 –
- Scientists belonging to a German–Malagasy expedition announce the discovery of Brookesia nana, a lizard found in Madagascar. The male's body spanning only 13.5 millimetres (0.5 in), it is potentially the smallest reptile on Earth. (BBC)
- 22 January 2021 – COVID-19 pandemic
- A panel of scientists that advises the British government announces that a variant first discovered in the United Kingdom is 30% more deadly than the original SARS-CoV-2 virus. (Forbes)
Portals