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...)
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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...)
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...)
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...)
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...)
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...)
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...)
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...)
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...)
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...)