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Michiel Van Der Klis
Michiel Baldur Maximiliaan van der Klis (born 9 June 1953) is a Dutch astronomer best known for his work on extreme 'pairings' of stars called X-ray binaries, more particularly his explanation of the occurrence of quasi-periodic oscillations (QPOs) in these systems and his co-discovery of the first millisecond X-ray pulsar. In the 1980s he gained worldwide fame with his investigation of QPOs. His revolutionary discoveries have had an enormous impact in his field of research; in effect, they have made it what it is today. Van der Klis pioneered special mathematical analysis techniques that are now regarded as the “gold standard” within his discipline. Research Van der Klis's research focuses on X-ray binaries, pairs of stars orbiting each other that emit X-ray radiation. Some binary star systems contain a compact object like a neutron star or a black hole. By studying the dynamics of materials in the vicinity of such objects one can learn about their mass, radius and rotational ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Hague
The Hague ( ) is the capital city of the South Holland province of the Netherlands. With a population of over half a million, it is the third-largest city in the Netherlands. Situated on the west coast facing the North Sea, The Hague is the country's administrative centre and its seat of government, and has been described as the country's ''de facto'' capital since the time of the Dutch Republic, while Amsterdam is the official capital of the Netherlands. The Hague is the core municipality of the COROP, Greater The Hague urban area containing over 800,000 residents, and is also part of the Rotterdam–The Hague metropolitan area, which, with a population of approximately 2.6 million, is the largest metropolitan area of the Netherlands. The city is also part of the Randstad region, one of the largest conurbations in Europe. The Hague is the seat of the Cabinet of the Netherlands, Cabinet, the States General of the Netherlands, States General, the Supreme Court of the Neth ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Black Hole
A black hole is a massive, compact astronomical object so dense that its gravity prevents anything from escaping, even light. Albert Einstein's theory of general relativity predicts that a sufficiently compact mass will form a black hole. The boundary (topology), boundary of no escape is called the event horizon. A black hole has a great effect on the fate and circumstances of an object crossing it, but has no locally detectable features according to general relativity. In many ways, a black hole acts like an ideal black body, as it reflects no light. Quantum field theory in curved spacetime predicts that event horizons emit Hawking radiation, with thermal radiation, the same spectrum as a black body of a temperature inversely proportional to its mass. This temperature is of the Orders of magnitude (temperature), order of billionths of a kelvin for stellar black holes, making it essentially impossible to observe directly. Objects whose gravitational fields are too strong for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Royal Netherlands Academy Of Arts And Sciences
The Royal Netherlands Academy of Arts and Sciences (, KNAW) is an organization dedicated to the advancement of science and literature in the Netherlands. The academy is housed in the Trippenhuis in Amsterdam. In addition to various advisory and administrative functions it operates a number of research institutes and awards many prizes, including the Lorentz Medal in theoretical physics, the Dr Hendrik Muller Prize for Behavioural and Social Science and the Heineken Prizes. Main functions The academy advises the Dutch government on scientific matters. While its advice often pertains to genuine scientific concerns, it also counsels the government on such topics as policy on careers for researchers or the Netherlands' contribution to major international projects. The academy offers solicited and unsolicited advice to parliament, ministries, universities and research institutes, funding agencies and international organizations. * Advising the government on matters related to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Space Research And Technology Centre
The European Space Research and Technology Centre (ESTEC) is the European Space Agency's main technology development and test centre for spacecraft and space technology. It is situated in Noordwijk, South Holland, in the western Netherlands, although several kilometers off the village but immediately linked to the most Northern district of the nearby town Katwijk. At ESTEC, about 2500 engineers, technicians and scientists work hands-on with mission design, spacecraft and space technology. ESTEC provides extensive testing facilities to verify the proper operation of spacecraft, such as the Large Space Simulator (LSS), acoustic and electromagnetic testing bays, multi-axis vibration tables and the ESA Propulsion Laboratory (EPL). Prior to launch, all of the equipment that ESA launches is tested in some degree at ESTEC, other than those tested at national space centers of ESA member countries. The Space Expo is ESTEC's visitors centre. It has a permanent exhibition about space explor ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
European Space Agency
The European Space Agency (ESA) is a 23-member International organization, international organization devoted to space exploration. With its headquarters in Paris and a staff of around 2,547 people globally as of 2023, ESA was founded in 1975 in the context of European integration. Its 2025 annual budget was €7.7 billion. The ESA Human and Robotic Exploration programme includes human spaceflight (mainly through participation in the International Space Station programme); as well as the launch and operation of missions to Mars and Moon. Further activities include science missions to Jupiter, Mercury, the Sun, Earth observation, Asteroid impact avoidance and Telecommunications missions, designing launch vehicles; and maintaining Europe's Spaceport, the Guiana Space Centre at Kourou (French Guiana). Further programmes include space safety, satellite navigation, applications and commercialisation. The main European launch vehicle Ariane 6 is operated through Arianespace ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nature (journal)
''Nature'' is a British weekly scientific journal founded and based in London, England. As a multidisciplinary publication, ''Nature'' features Peer review, peer-reviewed research from a variety of academic disciplines, mainly in science and technology. It has core editorial offices across the United States, continental Europe, and Asia under the international scientific publishing company Springer Nature. ''Nature'' was one of the world's most cited scientific journals by the Science Edition of the 2022 ''Journal Citation Reports'' (with an ascribed impact factor of 50.5), making it one of the world's most-read and most prestigious academic journals. , it claimed an online readership of about three million unique readers per month. Founded in the autumn of 1869, ''Nature'' was first circulated by Norman Lockyer and Alexander MacMillan (publisher), Alexander MacMillan as a public forum for scientific innovations. The mid-20th century facilitated an editorial expansion for the j ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
SAX J1808
Sax or SAX may refer to: * Saxophone (or sax), a family of woodwind instruments People * Adolphe Sax, inventor of the saxophone * Oett M. Mallard (1915–1986), also known as Sax Mallard, Chicago-based jazz saxophonist and bandleader * Lincoln Thompson (1949–1999), Jamaican reggae singer, musician and songwriter also known as Sax * Sax (surname) * Sax Rohmer, pen name of Arthur Henry Sarsfield Ward (1883–1959), English novelist best known for creating the villain Fu Manchu Places * 3534 Sax, an asteroid * Sax, a village in the Sennwald municipality in Switzerland * Sax, Alicante, a municipality in Spain * Sax, Minnesota, United States, an unincorporated community * Shanxi, a province of China (Guobiao abbreviation SAX) Other * Sax (cigarette), an Italian brand * "Sax" (song), a 2015 song released by English recording artist Fleur East *Seax, also spelled sax, an ancient Germanic, single-edged knife *Simple API for XML, an event-driven parsing model for XML *Baron of Sax, l ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Rudy Wijnands
Rudy Wijnands (born 1971) is a Dutch astrophysicist. He is professor of Observational High-Energy Astrophysics at the University of Amsterdam. Academic career Since 2004 Wijnands has been part of the faculty with the Anton Pannekoek Institute for Astronomy at the University of Amsterdam in the Netherlands. In 2008 he was appointed associate professor, and in 2017 full professor. Before that, he worked at the University of St Andrews in Scotland, and MIT in the United States. He received his PhD from the University of Amsterdam in 1999 with a thesis entitled "Millisecond phenomena in X-ray binaries". Research His research focuses on the accretion of matter onto neutron stars and black holes, which are very compact stellar remnants. He uses X-ray space telescopes such as Chandra X-ray Observatory and XMM-Newton to observe the X-ray emission from these objects. In particular he studies neutron stars and black holes when they are accreting at very low rates. He also investigates th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galaxy
A galaxy is a Physical system, system of stars, stellar remnants, interstellar medium, interstellar gas, cosmic dust, dust, and dark matter bound together by gravity. The word is derived from the Ancient Greek, Greek ' (), literally 'milky', a reference to the Milky Way galaxy that contains the Solar System. Galaxies, averaging an estimated 100 million stars, range in size from dwarf galaxy, dwarfs with less than a thousand stars, to the List of largest galaxies, largest galaxies known – Type-cD galaxy, supergiants with one hundred 10^12, trillion stars, each orbiting its galaxy's centre of mass. Most of the mass in a typical galaxy is in the form of dark matter, with only a few per cent of that mass visible in the form of stars and nebulae. Supermassive black holes are a common feature at the centres of galaxies. Galaxies are categorised according to their visual morphology (astronomy), morphology as elliptical galaxy, elliptical, Spiral galaxy, spiral, or irregular galaxy ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milky Way
The Milky Way or Milky Way Galaxy is the galaxy that includes the Solar System, with the name describing the #Appearance, galaxy's appearance from Earth: a hazy band of light seen in the night sky formed from stars in other arms of the galaxy, which are so far away that they cannot be individually distinguished by the naked eye. The Milky Way is a barred spiral galaxy with a Galaxy#Isophotal diameter, D25 isophotal diameter estimated at , but only about 1,000 light-years thick at the spiral arms (more at the bulge). Recent simulations suggest that a dark matter area, also containing some visible stars, may extend up to a diameter of almost 2 million light-years (613 kpc). The Milky Way has several List of Milky Way's satellite galaxies, satellite galaxies and is part of the Local Group of galaxies, forming part of the Virgo Supercluster which is itself a component of the Laniakea Supercluster. It is estimated to contain 100–400 billion stars and at least that number of pla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
General Relativity
General relativity, also known as the general theory of relativity, and as Einstein's theory of gravity, is the differential geometry, geometric theory of gravitation published by Albert Einstein in 1915 and is the current description of gravitation in modern physics. General theory of relativity, relativity generalizes special relativity and refines Newton's law of universal gravitation, providing a unified description of gravity as a geometric property of space and time in physics, time, or four-dimensional spacetime. In particular, the ''curvature of spacetime'' is directly related to the energy and momentum of whatever is present, including matter and radiation. The relation is specified by the Einstein field equations, a system of second-order partial differential equations. Newton's law of universal gravitation, which describes gravity in classical mechanics, can be seen as a prediction of general relativity for the almost flat spacetime geometry around stationary mass ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cosmology
Cosmology () is a branch of physics and metaphysics dealing with the nature of the universe, the cosmos. The term ''cosmology'' was first used in English in 1656 in Thomas Blount's ''Glossographia'', with the meaning of "a speaking of the world". In 1731, German philosopher Christian Wolff used the term cosmology in Latin (''cosmologia'') to denote a branch of metaphysics that deals with the general nature of the physical world. Religious or mythological cosmology is a body of beliefs based on mythological, religious, and esoteric literature and traditions of creation myths and eschatology. In the science of astronomy, cosmology is concerned with the study of the chronology of the universe. Physical cosmology is the study of the observable universe's origin, its large-scale structures and dynamics, and the ultimate fate of the universe, including the laws of science that govern these areas. It is investigated by scientists, including astronomers and physicists, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
