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Infrared Optical Telescope Array
The Infrared Optical Telescope Array (IOTA) was a stellar interferometer array. IOTA began with an agreement in 1988 among five Institutions, the Smithsonian Astrophysical Observatory, Harvard University, the University of Massachusetts Amherst, the University of Wyoming, and MIT/Lincoln Laboratory, to build a two-telescope stellar interferometer for the purpose of making fundamental astrophysical observations, and also as a prototype instrument on which they could perfect techniques which could later lead to the development of a larger, more powerful array. On site construction went on for all 1993 and 1994, with first fringes in December 1993. It is located at Fred Lawrence Whipple Observatory. In 2000 the third telescope came online providing closure phase observations, allowing aperture synthesis imaging to be performed for the first time at IOTA. The array was decommissioned and disassembled in summer 2006 due to lack of funding. See also * List of astronomical interferome ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Stellar Interferometer
An astronomical interferometer or telescope array is a set of separate telescopes, mirror segments, or radio telescope antennas that work together as a single telescope to provide higher resolution images of astronomical objects such as stars, nebulas and galaxies by means of interferometry. The advantage of this technique is that it can theoretically produce images with the angular resolution of a huge telescope with an aperture equal to the separation between the component telescopes. The main drawback is that it does not collect as much light as the complete instrument's mirror. Thus it is mainly useful for fine resolution of more luminous astronomical objects, such as close binary stars. Another drawback is that the maximum angular size of a detectable emission source is limited by the minimum gap between detectors in the collector array. Interferometry is most widely used in radio astronomy, in which signals from separate radio telescopes are combined. A mathematical sign ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Smithsonian Astrophysical Observatory
The Smithsonian Astrophysical Observatory (SAO) is a research institute of the Smithsonian Institution, concentrating on astrophysical studies including galactic and extragalactic astronomy, cosmology, solar, earth and planetary sciences, theory and instrumentation, using observations at wavelengths from the highest energy gamma rays to the radio, along with gravitational waves. Established in Washington, D.C., in 1890, the SAO moved its headquarters in 1955 to Cambridge, Massachusetts, where its research is a collaboration with the Harvard College Observatory (HCO) and the Harvard University Department of Astronomy. In 1973, the Smithsonian and Harvard formalized the collaboration as the Center for Astrophysics , Harvard & Smithsonian (CfA) under a single Director. History Samuel Pierpont Langley, the third Secretary of the Smithsonian, founded the Smithsonian Astrophysical Observatory on the south yard of the Smithsonian Castle (on the U.S. National Mall) on March 1 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Harvard University
Harvard University is a private Ivy League research university in Cambridge, Massachusetts. Founded in 1636 as Harvard College and named for its first benefactor, the Puritan clergyman John Harvard, it is the oldest institution of higher learning in the United States and one of the most prestigious and highly ranked universities in the world. The university is composed of ten academic faculties plus Harvard Radcliffe Institute. The Faculty of Arts and Sciences offers study in a wide range of undergraduate and graduate academic disciplines, and other faculties offer only graduate degrees, including professional degrees. Harvard has three main campuses: the Cambridge campus centered on Harvard Yard; an adjoining campus immediately across Charles River in the Allston neighborhood of Boston; and the medical campus in Boston's Longwood Medical Area. Harvard's endowment is valued at $50.9 billion, making it the wealthiest academic institution in the world. Endowment inco ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Massachusetts Amherst
The University of Massachusetts Amherst (UMass Amherst, UMass) is a public research university in Amherst, Massachusetts and the sole public land-grant university in Commonwealth of Massachusetts. Founded in 1863 as an agricultural college, it is the flagship and the largest campus in the University of Massachusetts system, as well as the first established. It is also a member of the Five College Consortium, along with four other colleges in the Pioneer Valley: Amherst College, Smith College, Mount Holyoke College, and Hampshire College. As of Fall 2022, UMass Amherst has an annual enrollment of more than 32,000 students, along with approximately 1,900 faculty members. It is the largest university in Massachusetts by campus size and second largest university by enrollment in Massachusetts, after Boston University. The university offers academic degrees in 109 undergraduate, 77 master's and 48 doctoral programs. Programs are coordinated in nine schools and colleges. The Universit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Wyoming
The University of Wyoming (UW) is a public land-grant research university in Laramie, Wyoming. It was founded in March 1886, four years before the territory was admitted as the 44th state, and opened in September 1887. The University of Wyoming is unusual in that its location within the state is written into the state's constitution. The university also offers outreach education in communities throughout Wyoming and online. The University of Wyoming consists of seven colleges: agriculture and natural resources, arts and sciences, business, education, engineering and applied sciences, health sciences, and law. The university offers over 120 undergraduate, graduate and certificate programs including Doctor of Pharmacy and Juris Doctor. It is classified among "R2: Doctoral Universities – High research activity". In addition to on-campus classes in Laramie, the university's Outreach School offers more than 41 degree, certificate and endorsement programs to distance learners ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lincoln Laboratory
The MIT Lincoln Laboratory, located in Lexington, Massachusetts, is a United States Department of Defense federally funded research and development center chartered to apply advanced technology to problems of national security. Research and development activities focus on long-term technology development as well as rapid system prototyping and demonstration. Its core competencies are in sensors, integrated sensing, signal processing for information extraction, decision-making support, and communications. These efforts are aligned within ten mission areas. The laboratory also maintains several field sites around the world. The laboratory transfers much of its advanced technology to government agencies, industry, and academia, and has launched more than 100 start-ups. History Origins At the urging of the United States Air Force, the Lincoln Laboratory was created in 1951 at the Massachusetts Institute of Technology (MIT) as part of an effort to improve the U.S. air defense syste ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferometer
Interferometry is a technique which uses the ''interference'' of superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, fiber optics, engineering metrology, optical metrology, oceanography, seismology, spectroscopy (and its applications to chemistry), quantum mechanics, nuclear and particle physics, plasma physics, remote sensing, biomolecular interactions, surface profiling, microfluidics, mechanical stress/strain measurement, velocimetry, optometry, and making holograms. Interferometers are devices that extract information from interference. They are widely used in science and industry for the measurement of microscopic displacements, refractive index changes and surface irregularities. In the case with most interferometers, light from a single source is split into two beams that travel in different optical paths, which are then combined again to produce in ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fred Lawrence Whipple Observatory
The Fred Lawrence Whipple Observatory is an American astronomy, astronomical observatory owned and operated by the Smithsonian Astrophysical Observatory (SAO); it is their largest field installation outside of their main site in Cambridge, Massachusetts. It is located near Amado, Arizona on the summit, a ridge and at the foot of Mount Hopkins (Arizona), Mount Hopkins. Research activities include imaging and spectroscopy of extragalactic, stellar, solar system and extra-solar bodies, as well as gamma ray, gamma-ray and cosmic ray, cosmic-ray astronomy. History In 1966, roadwork began on the current site with funding granted for the Smithsonian Mt. Hopkins Observatory. The Whipple 10-meter gamma-ray telescope was constructed in 1968. Formerly known as The Mount Hopkins Observatory, the observatory was renamed in late 1981 in honor of Fred Lawrence Whipple, noted planetary expert, space science pioneer, and director emeritus of SAO, under whose leadership the Arizona facility wa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Closure Phase
The closure phase is an observable quantity in imaging astronomical interferometry, which allowed the use of interferometry with very long baselines. It forms the basis of the self-calibration approach to interferometric imaging. The observable which is usually used in most "closure phase" observations is actually the complex quantity called the ''triple product'' (or ''bispectrum''). The closure phase is the phase (argument) of this complex quantity. History Roger Jennison developed this novel technique for obtaining information about visibility phases in an interferometer when delay errors are present. Although his initial laboratory measurements of closure phase had been done at optical wavelengths, he foresaw greater potential for his technique in radio interferometry. In 1958 he demonstrated its effectiveness with a radio interferometer, but it became widely used for long baseline radio interferometry only in 1974. A minimum of three antennas are required. This method was ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Aperture Synthesis
Aperture synthesis or synthesis imaging is a type of interferometry that mixes signals from a collection of telescopes to produce images having the same angular resolution as an instrument the size of the entire collection. At each separation and orientation, the lobe-pattern of the interferometer produces an output which is one component of the Fourier transform of the spatial distribution of the brightness of the observed object. The image (or "map") of the source is produced from these measurements. Astronomical interferometers are commonly used for high-resolution optical, infrared, submillimetre and radio astronomy observations. For example, the Event Horizon Telescope project derived the first image of a black hole using aperture synthesis. Technical issues Aperture synthesis is possible only if both the amplitude and the phase of the incoming signal are measured by each telescope. For radio frequencies, this is possible by electronics, while for optical frequencies, th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
List Of Astronomical Interferometers At Visible And Infrared Wavelengths
Here is a list of currently existing astronomical optical interferometers (i.e. operating from visible to mid-infrared wavelengths), and some parameters describing their performance. Current performance of ground-based interferometers Columns 2-5 determine the range of targets that can be observed and the range of science which can be done. Higher limiting magnitude means that the array can observe fainter sources. The limiting magnitude is determined by the atmospheric seeing, the diameters of the telescopes and the light lost in the system. A larger range of baselines means that a wider variety of science can be done and on a wider range of sources. Columns 6-10 indicate the approximate quality and total amount of science data the array is expected to obtain. This is per year, to account for the average number of cloud-free nights on which each array is operated. New interferometers and improvements to existing interferometers See also * Lists of telescopes * Photometr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Infrared Telescopes
An infrared telescope is a telescope that uses infrared light to detect celestial bodies. Infrared light is one of several types of radiation present in the electromagnetic spectrum. All celestial objects with a temperature above absolute zero emit some form of electromagnetic radiation. In order to study the universe, scientists use several different types of telescopes to detect these different types of emitted radiation in the electromagnetic spectrum. Some of these are gamma ray, x-ray, ultra-violet, regular visible light (optical), as well as infrared telescopes. Leading discoveries There were several key developments that led to the invention of the infrared telescope: * In 1800, William Herschel discovered infrared radiation. * In 1878, Samuel Pierpoint Langley created the first bolometer. This was a very sensitive instrument that could electrically detect incredibly small changes in temperature in the infrared spectrum. * Thomas Edison used an alternative technology, ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
