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Scattered Disc
The scattered disc (or scattered disk) is a distant circumstellar disc in the Solar System that is sparsely populated by icy small solar system bodies, which are a subset of the broader family of trans-Neptunian objects. The scattered-disc objects (SDOs) have orbital eccentricities ranging as high as 0.8, inclinations as high as 40°, and perihelia greater than . These extreme orbits are thought to be the result of gravitational "scattering" by the gas giants, and the objects continue to be subject to perturbation by the planet Neptune. Although the closest scattered-disc objects approach the Sun at about 30–35 AU, their orbits can extend well beyond 100 AU. This makes scattered objects among the coldest and most distant objects in the Solar System. The innermost portion of the scattered disc overlaps with a torus-shaped region of orbiting objects traditionally called the Kuiper belt, but its outer limits reach much farther away from the Sun and farther above and b ...
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Eris And Dysnomia2
Eris most often refers to: * Eris (mythology) or , the goddess of discord in Greek mythology * Eris (dwarf planet) Eris may also refer to: Fictional characters * Eris Vanserra, the eldest son of Beron, the High Lord of the Autumn Court from the ''A Court of Thorns and Roses'' series * Eris Morn, a character from the ''Destiny'' video game series * Eris the Deceiver, a character from ''The Grim Adventures of Billy & Mandy'' * Eris, a character from ''Star Trek Deep Space Nine'' episode "The Jem'Hadar" * Eris, a character in '' Sinbad: Legend of the Seven Seas'' * Eris, a character from the ''Asobi ni Iku yo!'' * Eris, a character in '' Drakengard 2'' * Eris, a character from Lego's Legends of Chima theme * Eris Boreas Greyrat, a character in Mushoku Tensei Other uses * Eris (confection), a traditional confection of Tabriz * Eris (fictional planet), a fictional planet in ''Damocles'' and its successor ''Mercenary III'' * ''Eris'' (spider), a genus of jumping spiders * Eris ...
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Oort Cloud
The Oort cloud (), sometimes called the Öpik–Oort cloud, first described in 1950 by the Dutch astronomer Jan Oort, is a theoretical concept of a cloud of predominantly icy planetesimals proposed to surround the Sun at distances ranging from 2,000 to 200,000 AU (0.03 to 3.2 light-years).The Oort cloud's outer limit is difficult to define as it varies over the millennia as different stars pass the Sun and thus is subject to variation. Estimates of its distance range from 50,000 to 200,000 au. It is divided into two regions: a disc-shaped inner Oort cloud (or Hills cloud) and a spherical outer Oort cloud. Both regions lie beyond the heliosphere and are in interstellar space. The Kuiper belt, the scattered disc and the detached objects, the other three reservoirs of trans-Neptunian objects, are less than one thousandth as far from the Sun as the Oort cloud. The outer limit of the Oort cloud defines the cosmographic boundary of the Solar System and the extent of the Sun' ...
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Near Earth Asteroid Tracking
Near-Earth Asteroid Tracking (NEAT) was a program run by NASA and the Jet Propulsion Laboratory, surveying the sky for near-Earth objects. NEAT was conducted from December 1995 until April 2007, at GEODSS on Hawaii (Haleakala-NEAT; 566), as well as at Palomar Observatory in California (Palomar-NEAT; 644). With the discovery of more than 40 thousand minor planets, NEAT has been one of the most successful programs in this field, comparable to the Catalina Sky Survey, LONEOS and Mount Lemmon Survey. NEAT was the successor to the Palomar Planet-Crossing Asteroid Survey (PCAS). History The original principal investigator was Eleanor F. Helin, with co-investigators Steven H. Pravdo and David L. Rabinowitz. NEAT has a cooperative agreement with the U.S. Air Force to use a GEODSS telescope located on Haleakala, Maui, Hawaii. GEODSS stands for Ground-based Electro-Optical Deep Space Surveillance and these wide field Air Force telescopes were designed to optically observe Ear ...
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229762 Gǃkúnǁʼhòmdímà
229762 Gǃkúnǁʼhòmdímà (provisional designation ) is a trans-Neptunian object and binary system from the extended scattered disc, located in the outermost region of the Solar System. It was discovered on 19 October 2007 by American astronomers Megan Schwamb, Michael Brown, and David Rabinowitz at the Palomar Observatory in California and measures approximately in diameter. This medium-sized TNO appears to be representative of a class of mid-sized objects under approximately 1000 km that have not collapsed into fully solid bodies. Its 100-kilometer moon was discovered by Keith Noll, Will Grundy, and colleagues with the Hubble Space Telescope in 2008, and named Gǃòʼé ǃHú. Names The name ''Gǃkúnǁʼhòmdímà'' is from the Juǀʼhoansi ( ǃKung) people of Namibia. Gǃkúnǁʼhòmdímà is the beautiful aardvark girl of Juǀʼhoan mythology, who sometimes appears in the stories of other San peoples as a python girl or elephant girl; she defends her people and pun ...
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Spacewatch
The Spacewatch Project is an astronomical survey that specializes in the study of minor planets, including various types of asteroids and comets at University of Arizona telescopes on Kitt Peak near Tucson, Arizona, in the United States. The Spacewatch Project has been active longer than any other similar currently active programs. Spacewatch was founded in 1980 by Tom Gehrels and Robert S. McMillan, and is currently led by astronomer Melissa Brucker at the University of Arizona. Spacewatch uses several telescopes on Kitt Peak for follow-up observations of near-Earth objects. The Spacewatch Project uses three telescopes of apertures 0.9-m, 1.8-m, and 2.3-m. These telescopes are located on Kitt Peak mountain in Arizona, and the first two are dedicated to the purpose of locating Near-Earth Objects (NEOs). The 36 inch (0.9 meter) telescope on Kitt Peak has been in use by Spacewatch since 1984, and since 2000 the 72 inch (1.8 meter) Spacewatch telescope. The 36 inch tel ...
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Mauna Kea
Mauna Kea ( or ; ; abbreviation for ''Mauna a Wākea''); is a dormant volcano on the island of Hawaii. Its peak is above sea level, making it the highest point in the state of Hawaii and second-highest peak of an island on Earth. The peak is about higher than Mauna Loa, its more massive neighbor. Mauna Kea is unusually topographically prominent for its height: its wet prominence is fifteenth in the world among mountains, at ; its dry prominence of is second in the world, only after Mount Everest This dry prominence is greater than Mount Everest's height above sea level of , and some authorities have labelled Mauna Kea the tallest mountain in the world, from its underwater base. It is about one million years old and thus passed the most active shield stage of life hundreds of thousands of years ago. In its current post-shield state, its lava is more viscous, resulting in a steeper profile. Late volcanism has also given it a much rougher appearance than its neighbori ...
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Astronomer
An astronomer is a scientist in the field of astronomy who focuses their studies on a specific question or field outside the scope of Earth. They observe astronomical objects such as stars, planets, moons, comets and galaxies – in either observational (by analyzing the data) or theoretical astronomy. Examples of topics or fields astronomers study include planetary science, solar astronomy, the origin or evolution of stars, or the formation of galaxies. A related but distinct subject is physical cosmology, which studies the Universe as a whole. Types Astronomers usually fall under either of two main types: observational and theoretical. Observational astronomers make direct observations of celestial objects and analyze the data. In contrast, theoretical astronomers create and investigate models of things that cannot be observed. Because it takes millions to billions of years for a system of stars or a galaxy to complete a life cycle, astronomers must observe sna ...
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Digital Image
A digital image is an image composed of picture elements, also known as ''pixels'', each with '' finite'', '' discrete quantities'' of numeric representation for its intensity or gray level that is an output from its two-dimensional functions fed as input by its spatial coordinates denoted with ''x'', ''y'' on the x-axis and y-axis, respectively. Depending on whether the image resolution is fixed, it may be of vector or raster type. Raster Raster images have a finite set of digital values, called ''picture elements'' or pixels. The digital image contains a fixed number of rows and columns of pixels. Pixels are the smallest individual element in an image, holding antiquated values that represent the brightness of a given color at any specific point. Typically, the pixels are stored in computer memory as a raster image or raster map, a two-dimensional array of small integers. These values are often transmitted or stored in a compressed form. Raster images can be created ...
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Digitizing
DigitizationTech Target. (2011, April). Definition: digitization. ''WhatIs.com''. Retrieved December 15, 2021, from https://whatis.techtarget.com/definition/digitization is the process of converting information into a digital (i.e. computer-readable) format.Collins Dictionary. (n.d.). Definition of 'digitize'. Retrieved December 15, 2021, from https://www.collinsdictionary.com/dictionary/english/digitize The result is the representation of an object, image, sound, document, or signal (usually an analog signal) obtained by generating a series of numbers that describe a discrete set of points or samples. The result is called '' digital representation'' or, more specifically, a '' digital image'', for the object, and ''digital form'', for the signal. In modern practice, the digitized data is in the form of binary numbers, which facilitates processing by digital computers and other operations, but digitizing simply means "the conversion of analog source material into a nume ...
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Telescope
A telescope is a device used to observe distant objects by their emission, absorption, or reflection of electromagnetic radiation. Originally meaning only an optical instrument using lenses, curved mirrors, or a combination of both to observe distant objects, the word ''telescope'' now refers to a wide range of instruments capable of detecting different regions of the electromagnetic spectrum, and in some cases other types of detectors. The first known practical telescopes were refracting telescopes with glass lenses and were invented in the Netherlands at the beginning of the 17th century. They were used for both terrestrial applications and astronomy. The reflecting telescope, which uses mirrors to collect and focus light, was invented within a few decades of the first refracting telescope. In the 20th century, many new types of telescopes were invented, including radio telescopes in the 1930s and infrared telescopes in the 1960s. Etymology The word ''telescope'' w ...
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Charge-coupled Device
A charge-coupled device (CCD) is an integrated circuit containing an array of linked, or coupled, capacitors. Under the control of an external circuit, each capacitor can transfer its electric charge to a neighboring capacitor. CCD sensors are a major technology used in digital imaging. In a CCD image sensor, pixels are represented by p-doped metal–oxide–semiconductor (MOS) capacitors. These MOS capacitors, the basic building blocks of a CCD, are biased above the threshold for inversion when image acquisition begins, allowing the conversion of incoming photons into electron charges at the semiconductor-oxide interface; the CCD is then used to read out these charges. Although CCDs are not the only technology to allow for light detection, CCD image sensors are widely used in professional, medical, and scientific applications where high-quality image data are required. In applications with less exacting quality demands, such as consumer and professional digital cameras, a ...
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Photographic Film
Photographic film is a strip or sheet of transparent film base coated on one side with a gelatin emulsion containing microscopically small light-sensitive silver halide crystals. The sizes and other characteristics of the crystals determine the sensitivity, contrast, and resolution of the film. The emulsion will gradually darken if left exposed to light, but the process is too slow and incomplete to be of any practical use. Instead, a very short exposure to the image formed by a camera lens is used to produce only a very slight chemical change, proportional to the amount of light absorbed by each crystal. This creates an invisible latent image in the emulsion, which can be chemically developed into a visible photograph. In addition to visible light, all films are sensitive to ultraviolet light, X-rays, gamma rays, and high-energy particles. Unmodified silver halide crystals are sensitive only to the blue part of the visible spectrum, producing unnatural-looking rendition ...
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