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Metsähovi Radio Observatory
The Metsähovi Radio Observatory is an astronomical observatory in Finland, affiliated with the Aalto University. Its main premises are in Metsähovi, Kirkkonummi, 35 kilometers west of the university's Otaniemi campus. The observatory currently operates a diameter radio telescope, and has an array of four dishes to serve as a compact interferometer called the 'Metsähovi Compact Array', as well as several smaller radio telescopes and instruments. The observatory is staffed by some 20 researchers, engineers, and students, mostly from Aalto University and the Finnish Centre for Astronomy with the ESO. The observatory has been operational since 1974 and active in the fields of: *Fundamental research in radio astronomy *Development of instruments needed in radio astronomy *Development of methods for radio astronomical measurements *Applied scientific computing *Space research *Education The current research focuses on variable quasars, active galaxies, solar observations, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Observatory
An observatory is a location used for observing terrestrial, marine, or celestial events. Astronomy, climatology/meteorology, geophysical, oceanography and volcanology are examples of disciplines for which observatories have been constructed. Historically, observatories were as simple as containing an astronomical sextant (for measuring the distance between stars) or Stonehenge (which has some alignments on astronomical phenomena). Astronomical observatories Astronomical observatories are mainly divided into four categories: space-based, airborne, ground-based, and underground-based. Ground-based observatories Ground-based observatories, located on the surface of Earth, are used to make observations in the radio and visible light portions of the electromagnetic spectrum. Most optical telescopes are housed within a dome or similar structure, to protect the delicate instruments from the elements. Telescope domes have a slit or other opening in the roof that can be opened during ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aalto University
Aalto University ( fi, Aalto-yliopisto; sv, Aalto-universitetet) is a public research university located in Espoo, Finland. It was established in 2010 as a merger of three major Finnish universities: the Helsinki University of Technology, the Helsinki School of Economics and the University of Art and Design Helsinki. The close collaboration between the scientific, business and arts communities is intended to foster multi-disciplinary education and research. The Finnish government, in 2010, set out to create a university that fosters innovation, merging the three institutions into one. The university is composed of six schools with close to 17,500 students and 4,000 staff members, making it Finland's second largest university. The main campus of Aalto University is located in Otaniemi, Espoo. Aalto University Executive Education operates in the district of Töölö, Helsinki. In addition to the Greater Helsinki area, the university also operates its Bachelor's Programme in Inter ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Kirkkonummi
Kirkkonummi (; sv, Kyrkslätt, , Sweden ) is a Municipalities of Finland, municipality of inhabitants () in southern Finland. The literal meaning of the words "''Kirkkonummi''" and "''Kyrkslätt''" in English language, English is "church heath". Geography The municipality is located just outside the Greater Helsinki, Helsinki Metropolitan Area, bordering the city of Espoo in the east. Other neighbouring municipalities are Vihti and Siuntio. The distance from the municipal centre to central Helsinki is some . Kirkkonummi also has excellent train and bus connections to other parts of the Greater Helsinki area, and many of its inhabitants commute daily to Helsinki. The municipality covers an area of of which is water. The population density is . In recent years, Kirkkonummi has faced the highest population growth rate in the country, at over 3% per annum. Major population centres in Kirkkonummi include the municipal centre, Masala, Kirkkonummi, Masala, Veikkola, Kantvik and the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Quasar
A quasar is an extremely Luminosity, luminous active galactic nucleus (AGN). It is pronounced , and sometimes known as a quasi-stellar object, abbreviated QSO. This emission from a galaxy nucleus is powered by a supermassive black hole with a mass ranging from millions to tens of billions of solar masses, surrounded by a gaseous accretion disc. Gas in the disc falling towards the black hole heats up because of friction and releases energy in the form of electromagnetic radiation. The radiant energy of quasars is enormous; the most powerful quasars have luminosity, luminosities thousands of times greater than that of a galaxy such as the Milky Way. Usually, quasars are categorized as a subclass of the more general category of AGN. The redshifts of quasars are of Expansion of the universe, cosmological origin. The term originated as a Contraction (grammar), contraction of "quasi-stellar ''[star-like]'' radio source"—because quasars were first identified during the 1950s as sour ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Active Galaxies
An active galactic nucleus (AGN) is a compact region at the center of a galaxy that has a much-higher-than-normal luminosity over at least some portion of the electromagnetic spectrum with characteristics indicating that the luminosity is not produced by stars. Such excess non-stellar emission has been observed in the radio, microwave, infrared, optical, ultra-violet, X-ray and gamma ray wavebands. A galaxy hosting an AGN is called an "active galaxy". The non-stellar radiation from an AGN is theorized to result from the accretion of matter by a supermassive black hole at the center of its host galaxy. Active galactic nuclei are the most luminous persistent sources of electromagnetic radiation in the universe, and as such can be used as a means of discovering distant objects; their evolution as a function of cosmic time also puts constraints on models of the cosmos. The observed characteristics of an AGN depend on several properties such as the mass of the central black hole, ... [...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] |
European VLBI Network
The European VLBI Network (EVN) is a network of radio telescopes located primarily in Europe and Asia, with additional antennas in South Africa and Puerto Rico, which performs very high angular resolution observations of cosmic radio sources using very-long-baseline interferometry (VLBI). The EVN is the most sensitive VLBI array in the world, and the only one capable of real-time observations. The Joint Institute for VLBI ERIC (JIVE) acts as the central organisation in the EVN, providing both scientific user support and a correlator facility. Very Long Baseline Interferometry (VLBI) achieves ultra-high angular resolution and is a multi-disciplinary technique used in astronomy, geodesy and astrometry. The EVN operates an open-sky policy, allowing anyone to propose an observation using the network EVN Telescopes The EVN network comprises 22 telescope facilities: Additionally the EVN often links with the UK-based 7-element Jodrell Bank MERLIN interferometer. It can also be conn ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Solar Eclipse Of March 20, 2015
A total solar eclipse occurred on March 20, 2015. A solar eclipse occurs when the Moon passes between Earth and the Sun, thereby totally or partly obscuring the image of the Sun for a viewer on Earth. A total solar eclipse occurs when the Moon's apparent diameter is larger than the Sun's, blocking all direct sunlight, turning day into darkness. Totality occurs in a narrow path across Earth's surface, with a partial solar eclipse visible over a surrounding region thousands of kilometres wide. This total solar eclipse is notable in that the path of totality passed over the North Pole. Totality was visible in the Faroe Islands and Svalbard. It had a magnitude of 1.0445. The longest duration of totality was 2 minutes and 47 seconds off the coast of the Faroe Islands. It was the last total solar eclipse visible in Europe until the eclipse of August 12, 2026. The track of totality passed across the North Atlantic and into the Arctic Ocean. Event The solar eclipse began at 08:30 GMT ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Astronomical Observatories
This is a 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 of atmo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Radio Telescopes
This is a list of radio telescopes – over one hundred – that are or have been used for radio astronomy. The list includes both single dishes and interferometric arrays. The list is sorted by region, then by name; unnamed telescopes are in reverse size order at the end of the list. The first radio telescope was invented in 1932, when Karl Jansky at Bell Telephone Laboratories observed radiation coming from the Milky Way. Africa Antarctica Asia Australia Europe North America South America Arctic Ocean Atlantic Ocean Indian Ocean Pacific Ocean Space-based Under construction or planned construction Proposed telescopes Gallery of big dishes File:FastTelescope*8sep2015.jpg, alt=Five hundred meter Aperture Spherical Telescope under construction, The 500 meter Five hundred meter Aperture Spherical Telescope (FAST), under construction, China (2016) File:GBT.png, alt=Green Bank Telescope, The 100 meter Green Bank Telescope, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
