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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 3500 to 3000 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 in academic and research institutions as well as in 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, and environmental protection.
Selected article
Phellinus ellipsoideus (formerly Fomitiporia ellipsoidea) is a species of polypore fungus in the family Hymenochaetaceae, a specimen of which produced the largest fungal fruit body ever recorded. Found in China, the fruit bodies produced by the species are brown, woody basidiocarps that grow on dead wood, where the fungus feeds as a saprotroph. The basidiocarps are perennial, allowing them to grow very large under favourable circumstances. They are resupinate, measuring 30 centimetres (12 in) or more in length, though typically extending less than a centimetre from the surface of the wood. P. ellipsoideus produces distinct ellipsoidal spores, after which it is named, and unusual setae. These two features allow it to be readily differentiated microscopically from other, similar species. Chemical compounds isolated from the species include several steroidal compounds. These may have pharmacological applications, but further research is needed.
The species was named in 2008 by Bao-Kai Cui and Yu-Cheng Dai based on collections made in Fujian Province. It was placed in the genus Fomitiporia, but later analysis suggests that it is more closely related to Phellinus species. It was revealed in 2011 that a very large fruit body, measuring up to 1,085 cm (427 in) in length, had been found on Hainan Island. The specimen, which was 20 years old, was estimated to weigh between 400 and 500 kilograms (880 and 1,100 lb). This was markedly larger than the previously largest recorded fungal fruit body, a specimen of Rigidoporus ulmarius found in the United Kingdom that had a circumference of 425 cm (167 in). The findings were formally published in September 2011, but attracted international attention from the mainstream press prior to this.
The hartebeest (/ˈhɑːrtəˌbiːst/; Alcelaphus buselaphus), also known as kongoni, is an African antelope. Eight subspecies have been described, including two sometimes considered to be independent species. A large antelope, the hartebeest stands just over 1 m (3.3 ft) at the shoulder, and has a typical head-and-body length of 200 to 250 cm (79 to 98 in). The weight ranges from 100 to 200 kg (220 to 440 lb). It has a particularly elongated forehead and oddly shaped horns, short neck, and pointed ears. Its legs, which often have black markings, are unusually long. The coat is generally short and shiny. Coat colour varies by the subspecies, from the sandy brown of the western hartebeest to the chocolate brown of the Swayne's hartebeest. Both sexes of all subspecies have horns, with those of females being more slender. Horns can reach lengths of 45–70 cm (18–28 in). Apart from its long face, the large chest and the sharply sloping back differentiate the hartebeest from other antelopes.
Gregarious animals, hartebeest form herds of 20 to 300 individuals. They are very alert and non-aggressive. They are primarily grazers, with their diets consisting mainly of grasses. Mating in hartebeest takes place throughout the year with one or two peaks, and depends upon the subspecies and local factors. Both males and females reach sexual maturity at one to two years of age. Gestation is eight to nine months long, after which a single calf is born. Births usually peak in the dry season. The lifespan is 12 to 15 years.
The Death and Panamint valleys area from space. The elliptical depression to the left is the Searles Lake basin, the smaller linear valley is Panamint Valley and the larger one is Death Valley. The mountain range between Death and Panamint valleys is the Panamint Range and the Black Mountains bound the other side of Death Valley. (NASA image)
The exposed geology of the Death Valley area presents a diverse and complex set of at least 23 formations of sedimentary units, two major gaps in the geologic record called unconformities, and at least one distinct set of related formations geologists call a group. The oldest rocks in the area that now includes Death Valley National Park are extensively metamorphosed by intense heat and pressure and are at least 1700 million years old. These rocks were intruded by a mass of granite 1400 Ma (million years ago) and later uplifted and exposed to nearly 500 million years of erosion.
Marine deposition occurred 1200 to 800 Ma, creating thick sequences of conglomerate, mudstone, and carbonate rock topped by stromatolites, and possibly glacial deposits from the hypothesized Snowball Earth event. Rifting thinned huge roughly linear parts of the supercontinent Rodinia enough to allow sea water to invade and divide its landmass into component continents separated by narrow straits. A passive margin developed on the edges of these new seas in the Death Valley region. Carbonate banks formed on this part of the two margins only to be subsided as the continental crust thinned until it broke, giving birth to a new ocean basin. An accretion wedge of clastic sediment then started to accumulate at the base of the submerged precipice, entombing the region's first known fossils of complex life. These sandy mudflats gave way about 550 Ma to a carbonate platform which lasted for the next 300 million years of Paleozoic time.
Herbert James Maryon, OBE, FSA, FIIC (9 March 1874 – 14 July 1965) was an English sculptor, conservator, goldsmith, archaeologist and authority on ancient metalwork. Maryon effectively had two careers. He practiced and taught sculpture until retiring in 1939, then worked as a conservator with the British Museum from 1944 until 1961. He is best known for his work on the Sutton Hoo ship-burial, which lead to his appointment as an Officer of the Order of the British Empire.
By his mid-twenties Maryon had attended three art schools, apprenticed in silversmithing with C. R. Ashbee, and worked in Henry Wilson's workshop. From 1900 to 1904 he served as the director of the Keswick School of Industrial Art, where he designed and exhibited numerous Arts and Crafts works. After moving to the University of Reading and then Durham University, he taught sculpture, metalwork, modelling, casting, and anatomy until 1939; he also designed the University of Reading War Memorial, among other commissions. Maryon published two books while teaching, including the standard Metalwork and Enamelling, and more than a dozen articles. He frequently led archaeological digs, and in 1935 discovered one of the oldest gold ornaments known in Britain while excavating the Kirkhaugh cairns.
Seen in orbit from the departing Space Shuttle Atlantis in 2009, flying Servicing Mission 4 (STS-125), the fifth and final Hubble mission
The Hubble Space Telescope (often referred to as HST or Hubble) is a space telescope that was launched into low Earth orbit in 1990 and remains in operation. It was not the first space telescope, but it is one of the largest and most versatile, well known both as a vital research tool and as a public relations boon for astronomy. The Hubble telescope is named after astronomer Edwin Hubble and is one of NASA's Great Observatories, along with the Compton Gamma Ray Observatory, the Chandra X-ray Observatory, and the Spitzer Space Telescope.
Hubble features a 2.4-meter (7.9 ft) mirror, and its four main instruments observe in the ultraviolet, visible, and near-infrared regions of the electromagnetic spectrum. Hubble's orbit outside the distortion of Earth's atmosphere allows it to capture extremely high-resolution images with substantially lower background light than ground-based telescopes. It has recorded some of the most detailed visible light images, allowing a deep view into space. Many Hubble observations have led to breakthroughs in astrophysics, such as determining the rate of expansion of the universe.
A surface weather analysis for the United States on October 21, 2006. By that time, Tropical Storm Paul was active (Paul later became a hurricane).
Surface weather analysis is a special type of weather map that provides a view of weather elements over a geographical area at a specified time based on information from ground-based weather stations.
Weather maps are created by plotting or tracing the values of relevant quantities such as sea level pressure, temperature, and cloud cover onto a geographical map to help find synoptic scale features such as weather fronts.
Male at the Smithsonian National Zoo
The king vulture (Sarcoramphus papa) is a large bird found in Central and South America. It is a member of the New World vulture family Cathartidae. This vulture lives predominantly in tropical lowland forests stretching from southern Mexico to northern Argentina. It is the only surviving member of the genus Sarcoramphus, although fossil members are known.
Large and predominantly white, the king vulture has gray to black ruff, flight, and tail feathers. The head and neck are bald, with the skin color varying, including yellow, orange, blue, purple, and red. The king vulture has a very noticeable orange fleshy caruncle on its beak. This vulture is a scavenger and it often makes the initial cut into a fresh carcass. It also displaces smaller New World vulture species from a carcass. King vultures have been known to live for up to 30 years in captivity.
The barn swallow (Hirundo rustica) is the most widespread species of swallow in the world. It is a distinctive passerine bird with blue upperparts and a long, deeply forked tail. It is found in Europe, Asia, Africa and the Americas. In Anglophone Europe it is just called the swallow; in Northern Europe it is the only common species called a "swallow" rather than a "martin".
There are six subspecies of barn swallow, which breed across the Northern Hemisphere. Four are strongly migratory, and their wintering grounds cover much of the Southern Hemisphere as far south as central Argentina, the Cape Province of South Africa, and northern Australia. Its huge range means that the barn swallow is not endangered, although there may be local population declines due to specific threats.
Chat Moss is a large area of peat bog that makes up 30 per cent of the City of Salford, Metropolitan Borough of Wigan and Warrington in Greater Manchester and Cheshire England. North of the Manchester Ship Canal and River Mersey, five miles (8 km) to the west of Manchester, it occupies an area of about 10.6 square miles (27.5 km2).
As it might be recognised today, Chat Moss is thought to be about 7,000 years old, but peat development seems to have begun there with the ending of the last ice age, about 10,000 years ago. The depth of peat ranges from 24 to 30 feet (7 to 9 m). A great deal of reclamation work has been carried out, particularly during the 19th century, but a large-scale network of drainage channels is still required to keep the land from reverting to bog. In 1958 workers extracting peat discovered the severed head of what is believed to be a Romano-British Celt, possibly a sacrificial victim, in the eastern part of the bog near Worsley.
Tyrannosaurus is a genus of coelurosaurian theropod dinosaur. The species Tyrannosaurus rex (rex meaning "king" in Latin), often called T. rex or colloquially T-Rex, is one of the most well-represented of the large theropods. Tyrannosaurus lived throughout what is now western North America, on what was then an island continent known as Laramidia. Tyrannosaurus had a much wider range than other tyrannosaurids. Fossils are found in a variety of rock formations dating to the Maastrichtian age of the upper Cretaceous period, 68 to 66 million years ago. It was the last known member of the tyrannosaurids, and among the last non-avian dinosaurs to exist before the Cretaceous–Paleogene extinction event.
Like other tyrannosaurids, Tyrannosaurus was a bipedal carnivore with a massive skull balanced by a long, heavy tail. Relative to its large and powerful hind limbs, Tyrannosaurus forelimbs were short but unusually powerful for their size and had two clawed digits. The most complete specimen measures up to 12.3 meters (40 feet) in length though T. rex could grow to lengths of over 12.3 m (40 ft), up to 3.66 m (12 ft) tall at the hips, and according to most modern estimates 8.4 metric tons (9.3 short tons) to 14 metric tons (15.4 short tons) in weight. Although other theropods rivaled or exceeded Tyrannosaurus rex in size, it is still among the largest known land predators and is estimated to have exerted the strongest bite force among all terrestrial animals. By far the largest carnivore in its environment, Tyrannosaurus rex was most likely an apex predator, preying upon hadrosaurs, armored herbivores like ceratopsians and ankylosaurs, and possibly sauropods. Some experts have suggested the dinosaur was primarily a scavenger. The question of whether Tyrannosaurus was an apex predator or a pure scavenger was among the longest debates in paleontology. Most paleontologists today accept that Tyrannosaurus was both an active predator and a scavenger.
Angkor Wat (/ˌæŋkɔːr ˈwɒt/; Khmer: អង្គរវត្ត, "City/Capital of Temples") is a temple complex in Cambodia and the largest religious monument in the world by land area, on a site measuring 162.6 hectares (1.626 km2; 402 acres). Originally constructed as a Hindu temple dedicated to the god Vishnu for the Khmer Empire, it was gradually transformed into a Buddhist temple towards the end of the 12th century as such it is also described as a "Hindu-Buddhist" temple. It was built by the Khmer King Suryavarman II in the early 12th century in Yaśodharapura (Khmer: យសោធរបុរៈ, present-day Angkor), the capital of the Khmer Empire, as his state temple and eventual mausoleum. Breaking from the Shaiva tradition of previous kings, Angkor Wat was instead dedicated to Vishnu. As the best-preserved temple at the site, it is the only one to have remained a significant religious centre since its foundation. The temple is at the top of the high classical style of Khmer architecture. It has become a symbol of Cambodia, appearing on its national flag, and it is the country's prime attraction for visitors.
Angkor Wat combines two basic plans of Khmer temple architecture: the temple-mountain and the later galleried temple. It is designed to represent Mount Meru, home of the devas in Hindu mythology: within a moat more than 5 kilometres (3 mi) long and an outer wall 3.6 kilometres (2.2 mi) long are three rectangular galleries, each raised above the next. At the centre of the temple stands a quincunx of towers. Unlike most Angkorian temples, Angkor Wat is oriented to the west; scholars are divided as to the significance of this. The temple is admired for the grandeur and harmony of the architecture, its extensive bas-reliefs, and for the numerous devatas adorning its walls.
The church at Waltham Abbey, where Hugh de Neville was buried
Hugh de Neville (died 1234) was the Chief Forester under the kings Richard I, John and Henry III of England; he was the sheriff for a number of counties. Related to a number of other royal officials as well as a bishop, Neville was a member of Prince Richard's household. After Richard became king in 1189, Neville continued in his service and accompanied him on the Third Crusade. Neville remained in the royal service following Richard's death in 1199 and the accession of King John to the throne, becoming one of the new king's favourites and often gambling with him. He was named in Magna Carta as one of John's principal advisers, and considered by a medieval chronicler to be one of King John's "evil counsellors". He deserted John after the French invasion of England in 1216 but returned to pledge his loyalty to John's son Henry III after the latter's accession to the throne later that year. Neville's royal service continued until his death in 1234, though by then he was a less significant figure than he had been at the height of his powers.
T. saccata male specimen on display at the Australian Museum
Thopha saccata, commonly known as the double drummer, is the largest Australian species of cicada and reputedly the loudest insect in the world. Documented by the Danish zoologist Johan Christian Fabricius in 1803, it was the first described and named cicada native to Australia. Its common name comes from the large dark red-brown sac-like pockets that the adult male has on each side of its abdomen—the "double drums"—that are used to amplify the sound it produces.
Broad-headed compared with other cicadas, the double drummer is mostly brown with a black pattern across the back of its thorax, and has red-brown and black underparts. The sexes are similar in appearance, though the female lacks the male's tymbals and sac-like covers. Found in sclerophyll forest in Queensland and New South Wales, adult double drummers generally perch high in the branches of large eucalypts. They emerge from the ground where they have spent several years as nymphs from November until March, and live for another four to five weeks. They appear in great numbers in some years, yet are absent in others.
Mars is the fourth planet from the Sun and the second-smallest planet in the Solar System, being larger than only Mercury. In English, Mars carries the name of the Roman god of war and is often referred to as the "Red Planet". The latter refers to the effect of the iron oxide prevalent on Mars's surface, which gives it a reddish appearance distinctive among the astronomical bodies visible to the naked eye. Mars is a terrestrial planet with a thin atmosphere, with surface features reminiscent of the impact craters of the Moon and the valleys, deserts and polar ice caps of Earth.
The days and seasons are comparable to those of Earth, because the rotational period as well as the tilt of the rotational axis relative to the ecliptic plane are similar. Mars is the site of Olympus Mons, the largest volcano and highest known mountain on any planet in the Solar System, and of Valles Marineris, one of the largest canyons in the Solar System. The smooth Borealis basin in the northern hemisphere covers 40% of the planet and may be a giant impact feature. Mars has two moons, Phobos and Deimos, which are small and irregularly shaped. These may be captured asteroids, similar to 5261 Eureka, a Mars trojan.
David Scott performs a stand-up EVA from Command Module Gumdrop, seen from docked Lunar Module Spider
Apollo 9 was a March 1969 human spaceflight, the third in NASA's Apollo program. Flown in low Earth orbit, it was the second crewed Apollo mission that the United States launched via a Saturn V rocket, and was the first flight of the full Apollo spacecraft: the command and service module (CSM) with the Lunar Module (LM). The mission was flown to qualify the LM for lunar orbit operations in preparation for the first Moon landing by demonstrating its descent and ascent propulsion systems, showing that its crew could fly it independently, then rendezvous and dock with the CSM again, as would be required for the first crewed lunar landing. Other objectives of the flight included firing the LM descent engine to propel the spacecraft stack as a backup mode (as would be required on the Apollo 13 mission), and use of the portable life support system backpack outside the LM cabin.
The three-man crew consisted of Commander James McDivitt, Command Module Pilot David Scott, and Lunar Module Pilot Rusty Schweickart. During the ten-day mission, they tested systems and procedures critical to landing on the Moon, including the LM engines, backpack life support systems, navigation systems and docking maneuvers.
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Selected image
The cloud pattern on Jupiter is the visible system of colored cloud tops in the atmosphere of the planet Jupiter, remarkable for its stability. Astronomers have given names to parts of this pattern, using the word zone for the light stripes and belt for the dark stripes along various latitudes. The pattern and intensity of its belts and zones are famously variable, often changing markedly from one opposition to the next.
The normal pattern of bands and zones is sometimes disrupted for a period of time, in events that astronomers call "disturbances". The longest-lived disturbance in recorded history was a "Southern Tropical Disturbance" (STropD) from 1901 until 1939, discovered by Percy B. Molesworth on February 28, 1901. It created a darkened feature over a range of longitudes in the normally bright Southern Tropical zone.
Selected biography
pronunciation (help·info)), April 15, 1452 – May 2, 1519) was an Italian polymath, having been a scientist, mathematician, engineer, inventor, anatomist, painter, sculptor, architect, botanist, musician and writer. Born as the illegitimate son of a notary, Piero da Vinci, and a peasant girl, Caterina, at Vinci in the region of Florence, Leonardo was educated in the studio of the renowned Florentine painter, Verrocchio. Much of his earlier working life was spent in the service of Ludovico il Moro in Milan. He later worked in Rome, Bologna and Venice, spending his final years in France at the home given to him by King François I.
Leonardo has often been described as the archetype of the "Renaissance man", a man whose seemingly infinite curiosity was equalled only by his powers of invention. He is widely considered to be one of the greatest painters of all time and perhaps the most diversely talented person ever to have lived.
It is primarily as a painter that Leonardo was and is renowned. Two of his works, the Mona Lisa and The Last Supper occupy unique positions as the most famous, most reproduced and most parodied portrait and religious painting of all time, their fame approached only by Michelangelo's Creation of Adam. Leonardo's drawing of the Vitruvian Man is also iconic. Perhaps fifteen of his paintings survive, the small number due to his constant, and frequently disastrous, experimentation with new techniques, and his chronic procrastination. Nevertheless, these few works together with his notebooks, which contain drawings, scientific diagrams, and his thoughts on the nature of painting, comprise a contribution to later generations of artists only rivalled by that of his contemporary, Michelangelo.
Did you know...
- ...that a laser harp (pictured) is an electronic musical instrument consisting of several laser beams that are blocked to produce sound?
- ...that Terminonatator ponteixensis is the type and only species described for Terminonatator, a genus of elasmosaurid plesiosaur from Late Cretaceous of Saskatchewan, Canada?
- ...necrotizing fasciitis is a rare infection of subcutaneous tissues that results in the necrosis of the flesh?
- ...Napalm-B, used in the Vietnam War, was synthesized with only three ingredients: polystyrene, gasoline, and benzene?
- ...Active noise canceling headphones, use circuitry to produce destructive wave interference to attenuate background sound?
Portals
- ^ Gardner, Helen (1970), Art through the Ages, Harcourt, Brace and World
- Vasari, Boltraffio, Castiglione, "Anonimo" Gaddiano, Berensen, Taine, Fuseli, Rio, Bortolon, etc. See specific quotations under heading "Leonardo, the legend".