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Catalina Sky Survey
Catalina Sky Survey (CSS; obs. code: 703) is an astronomical survey to discover comets and asteroids. It is conducted at the Steward Observatory's Catalina Station, located near Tucson, Arizona, in the United States. CSS focuses on the search for near-Earth objects, in particular on any potentially hazardous asteroid that may pose a threat of impact. Its counterpart in the southern hemisphere was the Siding Spring Survey (SSS), closed in 2013 due to loss of funding. CSS supersedes the photographic Bigelow Sky Survey. Mission The NEO Observations Program is a result of a United States 1998 congressional directive to NASA to begin a program to identify objects or larger to a confidence level of 90% or better. The Catalina Sky Survey, located at the Mount Lemmon Observatory in the Catalina Mountains north of Tucson, carries out searches for near-earth objects (NEOs), contributing to the congressionally-mandated goal. In addition to identifying impact risks, the projec ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Minor Planet
According to the International Astronomical Union (IAU), a minor planet is an astronomical object in direct orbit around the Sun that is exclusively classified as neither a planet nor a comet. Before 2006, the IAU officially used the term ''minor planet'', but that year's meeting IAU definition of planet, reclassified minor planets and comets into dwarf planets and Small Solar System body, small Solar System bodies (SSSBs).Press release, IAU 2006 General Assembly: Result of the IAU Resolution votes International Astronomical Union, August 24, 2006. Accessed May 5, 2008. In contrast to the eight official planets of the Solar System, all minor planets fail to clearing the neighborhood, clear their orbital neighborhood. Minor planets include asteroids (near- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Tucson
Tucson (; ; ) is a city in Pima County, Arizona, United States, and its county seat. It is the second-most populous city in Arizona, behind Phoenix, Arizona, Phoenix, with a population of 542,630 in the 2020 United States census. The Tucson metropolitan statistical area had 1.043 million residents in 2020 and forms part of the Tucson-Nogales combined statistical area. Tucson and Phoenix anchor the Arizona Sun Corridor. The city is southeast of Phoenix and north of the United States–Mexico border It is home to the University of Arizona. Major incorporated suburbs of Tucson include Oro Valley, Arizona, Oro Valley and Marana, Arizona, Marana northwest of the city, Sahuarita, Arizona, Sahuarita south of the city, and South Tucson, Arizona, South Tucson in an enclave south of downtown. Communities in the vicinity of Tucson (some within or overlapping the city limits) include Casas Adobes, Arizona, Casas Adobes, Catalina Foothills, Arizona, Catalina Foothills, Flowing Wells, A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
UBV Photometric System
__NOTOC__ The UBV photometric system (from ''Ultraviolet, Blue, Visual''), also called the Johnson system (or Johnson-Morgan system), is a photometric system usually employed for classifying stars according to their colors. It was the first standardized photometric system. The apparent magnitudes of stars in the system are often used to determine the color indices B−V and U−B, the difference between the B and V magnitudes and the U and B magnitudes respectively. The system is defined using a set of color optical filters in combination with an RMA 1P21 photomultiplier tube. The choice of colors on the blue end of the spectrum was assisted by the bias that photographic film has for those colors. It was introduced in the 1950s by American astronomers Harold Lester Johnson and William Wilson Morgan. A telescope and the telescope at McDonald Observatory were used to define the system. The filters that Johnson and Morgan used were Corning 9 863 for U and 3 384 for V. The ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exposure (photography)
In photography, exposure is the amount of light per unit area reaching a frame (photography), frame of photographic film or the surface of an electronic image sensor. It is determined by shutter speed, lens f-number, and scene luminance. Exposure is measured in unit of measurement, units of lux-seconds (symbol lxs), and can be computed from exposure value (EV) and scene luminance in a specified region. An "exposure" is a single shutter cycle. For example, a long-exposure photography, long exposure refers to a single, long shutter cycle to gather enough dim light, whereas a multiple exposure involves a series of shutter cycles, effectively layering a series of photographs in one image. The accumulated ''photometric exposure'' (''H''v) is the same so long as the total exposure time is the same. Definitions Radiant exposure Radiant exposure of a ''surface'', denoted ''H''e ("e" for "energetic", to avoid confusion with Photometry (optics), photometric quantities) and measured in , i ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Field Of View
The field of view (FOV) is the angle, angular extent of the observable world that is visual perception, seen at any given moment. In the case of optical instruments or sensors, it is a solid angle through which a detector is sensitive to electromagnetic radiation. It is further relevant in ''angle of view, photography''. Humans and animals In the context of human and primate vision, the term "field of view" is typically only used in the sense of a restriction to what is visible by external apparatus, like when wearing spectacles or virtual reality goggles. Note that eye movements are allowed in the definition but do not change the field of view when understood this way. If the analogy of the eye's retina working as a sensor is drawn upon, the corresponding concept in human (and much of animal vision) is the visual field. It is defined as "the number of degrees of visual angle during stable fixation of the eyes".Strasburger, Hans; Pöppel, Ernst (2002). Visual Field. In G. A ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Dark Current (physics)
In physics and in electronic engineering, dark current is the relatively small electric current that flows through photosensitive devices such as a photomultiplier tube, photodiode, or charge-coupled device even when no photons enter the device; it consists of the charges generated in the detector when no outside radiation is entering the detector. It is referred to as reverse bias leakage current in non-optical devices and is present in all diodes. Physically, dark current is due to the random generation of electrons and holes within the depletion region of the device. Dark current is one of the main sources for noise in image sensors such as charge-coupled devices. The pattern of different dark currents can result in a fixed-pattern noise; dark frame subtraction can remove an estimate of the mean fixed pattern, but there still remains a temporal noise, because the dark current itself has a shot noise Shot noise or Poisson noise is a type of noise which can be modeled by a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermoelectric Cooling
Thermoelectric cooling uses the Peltier effect to create a heat flux at the junction of two different types of materials. A Peltier cooler, heater, or thermoelectric heat pump is a Solid-state physics, solid-state active heat pump which transfers heat from one side of the device to the other, with consumption of electrical energy, depending on the direction of the current. Such an instrument is also called a Peltier device, Peltier heat pump, solid state refrigerator, or thermoelectric cooler (TEC) and occasionally a thermoelectric battery. It can be used either for heating or for cooling, although in practice the main application is cooling since heating can be achieved with simpler devices (with Joule heating). It can also be used as a temperature controller that either heats or cools. This technology is far less commonly applied to refrigeration than vapor-compression refrigeration is. The primary advantages of a Peltier cooler compared to a vapor-compression refrigerator are it ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Siding Spring Observatory
Siding Spring Observatory near Coonabarabran, New South Wales, Australia, part of the Research School of Astronomy & Astrophysics (RSAA) at the Australian National University (ANU), incorporates the Anglo-Australian Telescope along with a collection of other telescopes owned by the Australian National University, the University of New South Wales, and other institutions. The observatory is situated above sea level in the Warrumbungle National Park on Mount Woorat, also known as Siding Spring Mountain. Siding Spring Observatory is owned by the Australian National University (ANU) and is part of the Mount Stromlo and Siding Spring Observatories research school. More than 100 million worth of research equipment is located at the observatory. There are over 60 telescopes on site, though not all are operational. History The original Mount Stromlo Observatory was set up by the Commonwealth Government in 1924. After duty supplying optical components to the military in World W ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Uppsala Southern Schmidt Telescope
The Uppsala Schmidt Telescope is a Schmidt telescope located in Australia. It was moved to Siding Spring Observatory from Mount Stromlo Observatory in 1982. The instrument has been used to study galaxies, asteroids and comets. It was last dedicated to the Siding Spring Survey. The telescope had a field of view of just over 6° through the use of a correcting plate, making its field three times as large as that of the Anglo-Australian Telescope. It used a spherical rather than a parabolic mirror with 0.6 m correcting plate to achieve this. Photographic plates and film were used as detectors. History The Uppsala Schmidt Telescope was built in 1956 in Sweden. The telescope was originally located at the Mount Stromlo Observatory. It was operational there between 1957 and 1982. It took the first images ever recorded of the Sputnik satellite in 1957. The telescope was modernised in 2000 and 2001 to include the experimental use of Charge-coupled devices (CCDs) which are ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Santa Catalina Mountains
The Santa Catalina Mountains, commonly referred to as the Catalina Mountains or the Catalinas, are north and northeast of Tucson in Arizona, United States, on Tucson's north perimeter. The mountain range is the most prominent in the Tucson area, with the highest average elevation. The highest point in the Catalinas is Mount Lemmon at an elevation of above sea level and receives of precipitation annually. Originally known by the Tohono O'odham Nation as Babad Do'ag, the Catalinas were later named in 1697 by Italian Jesuit priest Eusebio Francisco Kino in honor of St. Catherine who was the patron saint of Kino's oldest sister. The Catalinas are part of the Santa Catalina Ranger District located in the Coronado National Forest, and also include the Pusch Ridge Wilderness Area. The mountain range is considered a prominent range in the Madrean sky islands, and partially delimits the mountain ranges in the northwest of the sky island region; lower elevation bajadas associated ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Mount Bigelow (Arizona)
Mount Bigelow is a mountain in the Santa Catalina Mountains of Arizona, United States. It is home to the astronomical observing facility Catalina Station which operates the 61" Kuiper Telescope owned by the Steward Observatory of the University of Arizona The University of Arizona (Arizona, U of A, UArizona, or UA) is a Public university, public Land-grant university, land-grant research university in Tucson, Arizona, United States. Founded in 1885 by the 13th Arizona Territorial Legislature, it .... It is one of the telescopes used by students at Astronomy Camp. References External links * * {{DEFAULTSORT:Bigelow Landforms of Pima County, Arizona Mountains of Pima County, Arizona ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Schmidt Camera
A Schmidt camera, also referred to as the Schmidt telescope, is a catadioptric astrophotographic telescope designed to provide wide fields of view with limited aberrations. The design was invented by Bernhard Schmidt in 1930. Some notable examples are the Samuel Oschin telescope (formerly Palomar Schmidt), the UK Schmidt Telescope and the ESO Schmidt; these provided the major source of all-sky photographic imaging from 1950 until 2000, when electronic detectors took over. A recent example is the Kepler space telescope exoplanet finder. Other related designs are the Wright camera and Lurie–Houghton telescope. Invention and design The Schmidt camera was invented by Estonian-German optician Bernhard Schmidt in 1930. Its optical components are an easy-to-make spherical primary mirror, and an aspherical correcting lens, known as a Schmidt corrector plate, located at the center of curvature of the primary mirror. The film or other detector is placed inside the camera, a ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
