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Ventspils International Radio Astronomy Centre
Ventspils International Radio Astronomy Centre ( – ''VIRAC'') is an ex-Soviet radio astronomy installation 30 km north of Ventspils, Latvia, on the coast of the Baltic Sea in Ance parish. The installation was secret until 1993 after Latvia regained independence. It was taken over by the Latvian Academy of Sciences after the withdrawal of the Soviet Army in 1994. Since then, two of the three radio telescopes have been repaired and renewed.Johannes Bach Rasmussen, Travel Guide: Traces of the Cold War Period', Nordic Council of Ministers, 2010, , p. 106. Description Located in woodlands near Irbene, in Ventspils Municipality, Latvia, the centre was founded in 1974 by the Soviet military. It originally consisted of a 32-metre telescope, along with two smaller telescopes and a communications centre, and was known as Zvezdochka, meaning "Little Star". It was possibly used by the KGB during the Cold War to spy on communications between Europe and the United States. It became a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Soviet Union
The Union of Soviet Socialist Republics. (USSR), commonly known as the Soviet Union, was a List of former transcontinental countries#Since 1700, transcontinental country that spanned much of Eurasia from 1922 until Dissolution of the Soviet Union, it dissolved in 1991. During its existence, it was the list of countries and dependencies by area, largest country by area, extending across Time in Russia, eleven time zones and sharing Geography of the Soviet Union#Borders and neighbors, borders with twelve countries, and the List of countries and dependencies by population, third-most populous country. An overall successor to the Russian Empire, it was nominally organized as a federal union of Republics of the Soviet Union, national republics, the largest and most populous of which was the Russian SFSR. In practice, Government of the Soviet Union, its government and Economy of the Soviet Union, economy were Soviet-type economic planning, highly centralized. As a one-party state go ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Focal Length
The focal length of an Optics, optical system is a measure of how strongly the system converges or diverges light; it is the Multiplicative inverse, inverse of the system's optical power. A positive focal length indicates that a system Convergence (optics), converges light, while a negative focal length indicates that the system Divergence (optics), diverges light. A system with a shorter focal length bends the Ray (optics), rays more sharply, bringing them to a focus in a shorter distance or diverging them more quickly. For the special case of a thin lens in air, a positive focal length is the distance over which initially Collimated beam, collimated (parallel) rays are brought to a Focus (optics), focus, or alternatively a negative focal length indicates how far in front of the lens a point source must be located to form a collimated beam. For more general optical systems, the focal length has no intuitive meaning; it is simply the inverse of the system's optical power. In mos ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
1974 Establishments In Latvia
Major events in 1974 include the aftermath of the 1973 oil crisis and the resignation of President of the United States, United States President Richard Nixon following the Watergate scandal. In the Middle East, the aftermath of the 1973 Yom Kippur War determined politics; following List of Prime Ministers of Israel, Israeli Prime Minister Golda Meir's resignation in response to high Israeli casualties, she was succeeded by Yitzhak Rabin. In Europe, the Turkish invasion of Cyprus, invasion and occupation of northern Cyprus by Turkey, Turkish troops initiated the Cyprus dispute, the Carnation Revolution took place in Portugal, the Greek junta's collapse paves the way for the establishment of a Metapolitefsi, parliamentary republic and Chancellor of Germany, Chancellor of West Germany Willy Brandt resigned following an Guillaume affair, espionage scandal surrounding his secretary Günter Guillaume. In sports, the year was primarily dominated by the 1974 FIFA World Cup, FIFA World ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Radio Telescopes
A radio telescope is a specialized antenna (radio), antenna and radio receiver used to detect radio waves from astronomical radio sources in the sky. Radio telescopes are the main observing instrument used in radio astronomy, which studies the radio frequency portion of the electromagnetic spectrum, just as optical telescopes are used to make observations in the visible light, visible portion of the spectrum in traditional optical astronomy. Unlike optical telescopes, radio telescopes can be used in the daytime as well as at night. Since astronomical radio sources such as planets, stars, nebulas and galaxy, galaxies are very far away, the radio waves coming from them are extremely weak, so radio telescopes require very large antennas to collect enough radio energy to study them, and extremely sensitive receiving equipment. Radio telescopes are typically large Parabolic antenna, parabolic ("dish") antennas similar to those employed in tracking and communicating with satellites an ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Astronomical Observatories Built In The Soviet Union
Astronomy is a natural science that studies astronomical object, celestial objects and the phenomena that occur in the cosmos. It uses mathematics, physics, and chemistry in order to explain their origin and their overall chronology of the Universe, evolution. Objects of interest include planets, natural satellite, moons, stars, nebulae, galaxy, galaxies, meteoroids, asteroids, and comets. Relevant phenomena include supernova explosions, gamma ray bursts, quasars, blazars, pulsars, and cosmic microwave background radiation. More generally, astronomy studies everything that originates beyond atmosphere of Earth, Earth's atmosphere. Cosmology is a branch of astronomy that studies the universe as a whole. Astronomy is one of the oldest natural sciences. The early civilizations in recorded history made methodical observations of the night sky. These include the Egyptian astronomy, Egyptians, Babylonian astronomy, Babylonians, Greek astronomy, Greeks, Indian astronomy, Indians, Ch ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Science And Technology In Latvia
Science is a systematic discipline that builds and organises knowledge in the form of testable hypotheses and predictions about the universe. Modern science is typically divided into twoor threemajor branches: the natural sciences, which study the physical world, and the social sciences, which study individuals and societies. While referred to as the formal sciences, the study of logic, mathematics, and theoretical computer science are typically regarded as separate because they rely on deductive reasoning instead of the scientific method as their main methodology. Meanwhile, applied sciences are disciplines that use scientific knowledge for practical purposes, such as engineering and medicine. The history of science spans the majority of the historical record, with the earliest identifiable predecessors to modern science dating to the Bronze Age in Egypt and Mesopotamia (). Their contributions to mathematics, astronomy, and medicine entered and shaped the Greek natural philo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bradt Travel Guides
Bradt Travel Guides is a publisher of travel guides founded in 1974 by Hilary Bradt and her husband George, who co-wrote the first Bradt Guide on a river barge on a tributary of the Amazon. Since then Bradt has grown into a leading independent travel publisher, with growth particularly in the last decade. It has a reputation for tackling destinations overlooked by other guide book publishers. Bradt guides have been cited by ''The Independent'' as covering "parts of the world other travel publishers don't reach", and nearly two-thirds of the guides on the publisher's list have no direct competition in English from other travel publishers. These include guides to parts of Asia, Latin America and Africa, in particular, which traditionally have not been widely covered by guidebook publishers, or do not have a long history of tourism. Bradt also has an extensive list of regional European guides to destinations such as the Peloponnese, the Vendée and the Basque Country. The guides ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Astronomical Observatories
This is a partial list of astronomical observatories ordered by name, along with initial dates of operation (where an accurate date is available) and location. The list also includes a final year of operation for many observatories that are no longer in operation. While other sciences, such as volcanology and meteorology, also use facilities called observatories for research and observations, this list is limited to observatories that are used to observe celestial objects. Astronomical observatories are mainly divided into four categories: space-based, airborne, ground-based, and underground-based. Many modern telescopes and observatories are located in space to observe astronomical objects in wavelengths of the electromagnetic spectrum that cannot penetrate the Earth's atmosphere (such as ultraviolet radiation, X-rays, and gamma rays) and are thus impossible to observe using ground-based telescopes. Being above the atmosphere, these space observatories can also avoid the effects ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Low-Frequency Array (LOFAR)
The Low-Frequency Array (LOFAR) is a large radio telescope, with an antenna network located mainly in the Netherlands, and spreading across 7 other European countries as of 2019. Originally designed and built by ASTRON, the Netherlands Institute for Radio Astronomy, it was first opened by Beatrix of the Netherlands, Queen Beatrix of The Netherlands in 2010, and has since been operated by ASTRON on behalf first of the International LOFAR Telescope (ILT) partnership and now of the LOFAR European Research Infrastructure Consortium, ERIC by ASTRON. LOFAR consists of a vast array of omnidirectional radio antennas using a modern concept, in which the signals from the separate antennas are not connected directly electrically to act as a single large antenna, as they are in most array antennas. Instead, the LOFAR dipole antennas (of two types) are distributed in stations, within which the antenna signals can be partly combined in analogue electronics, then digitised, then combined again a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Very-long-baseline Interferometry
Very-long-baseline interferometry (VLBI) is a type of astronomical interferometry used in radio astronomy. In VLBI a signal from an astronomical radio source, such as a quasar, is collected at multiple radio telescopes on Earth or in space. The distance between the radio telescopes is then calculated using the time difference between the arrivals of the radio signal at different telescopes. This allows observations of an object that are made simultaneously by many radio telescopes to be combined, emulating a telescope with a size equal to the maximum separation between the telescopes. Data received at each antenna in the array include arrival times from a local atomic clock, such as a hydrogen maser. At a later time, the data are correlated with data from other antennas that recorded the same radio signal, to produce the resulting image. The resolution achievable using interferometry is proportional to the observing frequency. The VLBI technique enables the distance between t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ukraine
Ukraine is a country in Eastern Europe. It is the List of European countries by area, second-largest country in Europe after Russia, which Russia–Ukraine border, borders it to the east and northeast. Ukraine also borders Belarus to the north; Poland and Slovakia to the west; Hungary, Romania and Moldova to the southwest; and the Black Sea and the Sea of Azov to the south and southeast. Kyiv is the nation's capital and List of cities in Ukraine, largest city, followed by Kharkiv, Odesa, and Dnipro. Ukraine's official language is Ukrainian language, Ukrainian. Humans have inhabited Ukraine since 32,000 BC. During the Middle Ages, it was the site of early Slavs, early Slavic expansion and later became a key centre of East Slavs, East Slavic culture under the state of Kievan Rus', which emerged in the 9th century. Kievan Rus' became the largest and most powerful realm in Europe in the 10th and 11th centuries, but gradually disintegrated into rival regional powers before being d ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
