|
Sydney University Stellar Interferometer
The Sydney University Stellar Interferometer (SUSI) was an optical long baseline interferometer owned by The University of Sydney. It was located in the Paul Wild Observatory, 20 km west of Narrabri town in New South Wales, Australia. SUSI was initially proposed by Australian astronomer John Davis (astronomer), John Davis in 1985, who led the project through to completion in 1993 and past his retirement in 1996 until his death in 2010. From then until its closure in 2017 it was led by Peter Tuthill (astronomer), Peter Tuthill, and used as a test facility for instruments for the CHARA Array. The Interferometry, interferometer had several siderostats, which collected and reflected starlight into the optical laboratory for interferometry via two vacuum pipes. Although mirrors at the siderostats were 20 cm in diameter, the effective aperture size was 14 cm as they operated at angles of about 45°. By selecting the different siderostats at different distances, the baseli ... [...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, 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 interference; two ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
CHARA Array
The CHARA (Center for High Angular Resolution Astronomy) array is an optical interferometer, located on Mount Wilson, California. The array consists of six telescopes operating as an astronomical interferometer. Construction was completed in 2003. CHARA is owned by Georgia State University (GSU). Functionality CHARA's six telescopes each have a one-meter diameter mirror to reflect light. They are spread across Mount Wilson to increase the angular resolution of the array. Each of the six telescopes provides a different image, to combine it into one image the light from each telescope is transported through vacuum tubes and fed into a single beam, where they are matched up to within one micron. This process is called interferometry, and allows the array to have the same resolving power as a telescope with a 330-meter mirror, and an angular resolution of 200 micro-arcseconds. History In 1984 CHARA was founded, and with financial support from the National Science Foundation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Milliarcseconds
A minute of arc, arcminute (abbreviated as arcmin), arc minute, or minute arc, denoted by the symbol , is a unit of angular measurement equal to of a degree. Since one degree is of a turn, or complete rotation, one arcminute is of a turn. The nautical mile (nmi) was originally defined as the arc length of a minute of latitude on a spherical Earth, so the actual Earth's circumference is very near . A minute of arc is of a radian. A second of arc, arcsecond (abbreviated as arcsec), or arc second, denoted by the symbol , is a unit of angular measurement equal to of a minute of arc, of a degree, of a turn, and (about ) of a radian. These units originated in Babylonian astronomy as sexagesimal (base 60) subdivisions of the degree; they are used in fields that involve very small angles, such as astronomy, optometry, ophthalmology, optics, navigation, land surveying, and marksmanship. To express even smaller angles, standard SI prefixes can be employed; the milliarcsec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Angular Resolution
Angular resolution describes the ability of any image-forming device such as an Optical telescope, optical or radio telescope, a microscope, a camera, or an Human eye, eye, to distinguish small details of an object, thereby making it a major determinant of image resolution. It is used in optics applied to light waves, in antenna (radio), antenna theory applied to radio waves, and in acoustics applied to sound waves. The colloquial use of the term "resolution" sometimes causes confusion; when an optical system is said to have a high resolution or high angular resolution, it means that the perceived distance, or actual angular distance, between resolved neighboring objects is small. The value that quantifies this property, ''θ,'' which is given by the Rayleigh criterion, is low for a system with a high resolution. The closely related term spatial resolution refers to the precision of a measurement with respect to space, which is directly connected to angular resolution in imaging ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Visible Spectrum
The visible spectrum is the spectral band, band of the electromagnetic spectrum that is visual perception, visible to the human eye. Electromagnetic radiation in this range of wavelengths is called ''visible light'' (or simply light). The optical spectrum is sometimes considered to be the same as the visible spectrum, but some authors define the term more broadly, to include the ultraviolet and infrared parts of the electromagnetic spectrum as well, known collectively as ''optical radiation''. A typical human eye will respond to wavelengths from about 380 to about 750 nanometers. In terms of frequency, this corresponds to a band in the vicinity of 400–790 Terahertz (unit), terahertz. These boundaries are not sharply defined and may vary per individual. Under optimal conditions, these limits of human perception can extend to 310 nm (ultraviolet) and 1100 nm (near infrared). The spectrum does not contain all the colors that the human visual system can distinguish. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Baseline (interferometry)
An astronomical interferometer or telescope array is a set of separate telescopes, mirror segments, or radio telescope antenna (radio), antennas that work together as a single telescope to provide higher resolution images of astronomical objects such as stars, nebulas and galaxy, 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, called ''baseline'', 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 radi ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siderostats
A heliostat () is a device that reflects sunlight toward a target, turning to compensate for the Sun's apparent motion. The reflector is usually a plane mirror. The target may be a physical object, distant from the heliostat, or a direction in space. To do this, the reflective surface of the mirror is kept perpendicular to the bisector of the angle between the directions of the Sun and the target as seen from the mirror. In almost every case, the target is stationary relative to the heliostat, so the light is reflected in a fixed direction. According to contemporary sources the heliostata, as it was called at first, was invented by Willem 's Gravesande (1688–1742). Other contenders are Giovanni Alfonso Borelli (1608–1679) and Daniel Gabriel Fahrenheit (1686–1736). A heliostat designed by George Johnstone Storey is in the Science Museum Group collection. Currently, most heliostats are used for daylighting or for the production of concentrated solar power, usually to ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Interferometry
Interferometry is a technique which uses the ''interference (wave propagation), interference'' of Superposition principle, superimposed waves to extract information. Interferometry typically uses electromagnetic waves and is an important investigative technique in the fields of astronomy, Optical fiber, fiber optics, engineering metrology, optical metrology, oceanography, seismology, spectroscopy (and its applications to chemistry), quantum mechanics, Nuclear physics, nuclear and particle physics, plasma physics, interactome, 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 ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Peter Tuthill (astronomer)
Peter G. Tuthill (born 18 Jan 1967) is an Australian astronomer who has pioneered the science of high-angular resolution astronomy, leading the development of aperture masking interferometry and astronomical optical interferometry. He is a professor of astrophysics at the School of Physics at the University of Sydney and was Director of the Sydney Institute for Astronomy (SIfA) of School from 2010 to 2015. Early life and education Tuthill was born in Sydney in 1967, and grew up in Warwick, Queensland. He attended the University of Queensland for an undergraduate degree in physics and ANU for Honours, before a PhD at Churchill College, Cambridge on the Cambridge Optical Aperture Synthesis Telescope. He won a Lindemann Trust Fellowship to do postdoctoral research at the University of California, Berkeley under Nobel Laureate Charles H. Townes, working on the Keck Aperture Masking Experiment. He returned to Australia to the University of Sydney, holding a succession of Fellow ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
University Of Sydney
The University of Sydney (USYD) is a public university, public research university in Sydney, Australia. Founded in 1850, it is the oldest university in both Australia and Oceania. One of Australia's six sandstone universities, it was one of the world's first universities to admit students solely on academic merit, and opened its doors to women on the same basis as men. The university comprises eight academic faculties and university schools, through which it offers bachelor, master and doctoral degrees. Five Nobel Prize, Nobel and two Crafoord Prize, Crafoord laureates have been affiliated with the university as graduates and faculty. The university has educated 8 Prime minister of Australia, Australian prime ministers, including incumbent Anthony Albanese; 2 Governor-General of Australia, governors-general of Australia; 13 Premier of New South Wales, premiers of New South Wales; and 26 justices of the High Court of Australia, including 5 Chief Justice of Australia, chief justic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
The Sydney Morning Herald
''The Sydney Morning Herald'' (''SMH'') is a daily Tabloid (newspaper format), tabloid newspaper published in Sydney, Australia, and owned by Nine Entertainment. Founded in 1831 as the ''Sydney Herald'', the ''Herald'' is the oldest continuously published newspaper in Australia and claims to be the most widely read masthead in the country. It is considered a newspaper of record for Australia. The newspaper is published in Compact (newspaper), compact print form from Monday to Saturday as ''The Sydney Morning Herald'' and on Sunday as its sister newspaper, ''The Sun-Herald'' and digitally as an Website, online site and Mobile app, app, seven days a week. The print edition of ''The Sydney Morning Herald'' is available for purchase from many retail outlets throughout the Sydney metropolitan area, most parts of regional New South Wales, the Australian Capital Territory and South East Queensland. Overview ''The Sydney Morning Herald'' publishes a variety of supplements, including ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
John Davis (astronomer)
John Davis may refer to: Academics * John A. G. Davis (1802–1840), professor at the University of Virginia School of Law, shot to death by a student *John Aubrey Davis Sr. (1912–2002), African American activist and political science professor * John Adelbert Davis (1871–1934), American bible college founder *John Davies (lecturer) or Davis (fl. 1816–1850), English chemist and lecturer *John Davis (academic) (1938–2017), English anthropologist and Warden of All Souls College, Oxford * John Emmeus Davis (born 1949), scholar, writer and community organizer * John J. Davis (theologian) (born 1936), American theologian, archaeologist, and Christian educator *John Jefferson Davis, professor of theology and Presbyterian pastor * John June Davis (1885–1965), American entomologist * John Warren Davis (college president) (1888–1980), African American educator, college administrator, and civil rights leader * John Davis (paediatrician) (1923–2025), British professor of paediatr ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
