Difference between revisions 1434705 and 1434860 on enwikiversity

[[Image:Brorfelde Schmidt Telescope.jpg|thumb|right|200px|The Schmidt Telescope at the former Brorfelde Observatory is now used by amateur astronomers. Credit: [[commons:User:Moeng|Mogens Engelund]].]]
A '''radiation telescope''' is an instrument designed to collect and focus radiation so as to make distant sources appear nearer.
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=[[Astronomy]]=
(contracted; show full)|year=2013
|url=http://en.wikipedia.org/wiki/Hubble_Space_Telescope
|accessdate=2013-01-22 }}</ref>

Most radiation telescopes, especially optical telescopes, combine a variety of lenses, mirrors, active and adaptive optics, filters, detectors, mounts, image processing, and observatories, in many locations.
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=
[[Physics/Optics/Actives|Active optics]]=
[[Image:GTC Active Optics Acutators.jpg|thumb|right|200px|Actuators are part of the active optics of the ''[[w:Gran Telescopio Canarias|Gran Telescopio Canarias]]''. Credit: .]]
“'''Active optics''' is a [[w:technology|technology]] used with [[w:reflecting telescope|reflecting telescope]]s developed in the 1980s<ref name=Hardy>{{ cite journal
|author=John W. Hardy
|title=Active optics: A new technology for the control of light
|year=1977
|month=June
(contracted; show full)|location=San Francisco, California
|month=12 October
|year=2014
|url=http://en.wikipedia.org/wiki/Active_optics
|accessdate=2014-12-25 }}</ref>
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=
[[Physics/Optics/Adaptives|Adaptive optics]]=
[[Image:GRAAL instrument.jpg|thumb|right|200px|This image shows some of the GRAAL instrument team inspecting GRAAL’s mechanical assembly. Credit: ESO.]]
'''Def.''' "[a]n optical system in telescopes that reduces atmospheric distortion by dynamically measuring and correcting wavefront aberrations in real time, often by using a deformable mirror"<ref name=AdaptiveOpticsWikt>{{ cite web
|title=adaptive optics, In: ''Wiktionary''
(contracted; show full)mprove the quality of images by compensating for turbulence in the lower layers of the atmosphere, up to an altitude of 1 kilometre. GRAAL, which will be installed on ESO’s Very Large Telescope (VLT) on Cerro Paranal in Chile, is designed to improve the vision of the VLT’s already excellent HAWK-I camera even further. Currently, HAWK-I operates without adaptive optics. Installing GRAAL will improve the sharpness of HAWK-I’s images, and reduce the exposure times needed by up to a factor of two.
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=
[[Instruments/Telescopes/Refracting|Refracting Ttelescopes]]=
[[Image:Kepschem.png|thumb|right|200px|This is a schematic of a Keplerian refracting telescope which uses two different sizes of planoconvex lenses. Credit: .]]
"The '''Keplerian Telescope''', invented by [[w:Johannes Kepler|Johannes Kepler]] in 1611, is an improvement on Galileo's design.<ref name=Tunnacliffe>{{ cite book
|title= Optics
|author= AH Tunnacliffe, JG Hirst
|year= 1996
|publisher= 
|location= Kent, England 
(contracted; show full)ve]] [[w:lens (optics)|lens]] '''1''' and some type of [[w:eyepiece|eyepiece]] '''2''' is used to gather more light than the human eye could collect on its own, focus it '''5''', and present the viewer with a [[w:brightness|brighter]], [[w:clarity|clearer]], and [[w:magnification|magnified]] [[w:virtual image|virtual image]] '''6'''."<ref name=RefractingTelescope/>
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=
[[Instruments/Telescopes/Reflecting|Reflecting telescopes]]=
[[Image:SOFIA 2.5M Primary Mirror.jpg|thumb|left|200px|The [[NASA]] logo on Bldg. 703 at the Dryden Aircraft Operations Facility in Palmdale, California, is reflected in the 2.5 m primary mirror of the SOFIA observatory's telescope. Credit: .]]
[[Image:Franklin reflector 24.jpg|right|thumb|200px|24 inch convertible Newtonian/Cassegrain reflecting telescopeis shown on display at the [[w:Franklin Institute|Franklin Institute]]. Credit: .]]
"A '''reflecting telescope''' (also called a '''reflector''') is an [[w:optical telescope|optical telescope]] which uses a single or combination of [[w:curved mirror|curved mirror]]s that reflect [[w:light|light]] and form an [[w:image|image]]."<ref name=ReflectingTelescope>{{ cite web
|title=Reflecting telescope, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=July 2,
|year=2012
|url=http://en.wikipedia.org/wiki/Reflecting_telescope
|accessdate=2012-07-07 }}</ref>
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=[[Instruments/Telescopes/Catadioptrics|Catadioptric telescopes]]=

'''Def.''' “optical systems that employ both refractive (dioptric) and reflective (catoptric) elements”<ref name=CatadioptricWikt>{{ cite web
|title=catadioptric, In: ''Wiktionary''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=9 October
|year=2013
|url=https://en.wiktionary.org/wiki/catadioptric
|accessdate=2014-12-25 }}</ref> are called '''catadioptric optical systems'''.

'''Def.''' “[t]he construction and use of catadioptric lenses and systems”<ref name=CatadioptricsWikt>{{ cite web
|title=catadioptrics, In: ''Wiktionary''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=9 October
|year=2013
|url=https://en.wiktionary.org/wiki/catadioptrics
|accessdate=2014-12-25 }}</ref> is called '''catadioptrics'''.

=[[Instruments/Telescopes/Dobsonians|Dobsonian telescopes]]=
[[Image:Red dobsonian.jpg|thumb|right|200px|This is a red Dobsonian telescope on display at Stellafane in the early 1980s. Credit: .]] 
"A '''Dobsonian telescope''' is an alt-azimuth mounted newtonian telescope design popularized by the [amateur astronomy] John Dobson starting in the 1960s. Dobson's telescopes featured a simplified mechanical design that was easy to manufacture from readily available components to create a large, portable, low-cost telescope. The design is optimized for visually observing faint deep sky objects such as nebulae. This type of observation requires a large objective diameter (i.e. light-gathering power) of relatively short focal length and portability for travel to relatively less light polluted locations.<ref name="books.google.com">[http://books.google.com/books?id=l2TNnHkdDpkC&pg=PA286&lr=#PPA287,M1 Jack Newton, Philip Teece - "'''The Guide to Amateur Astronomy'''" - Page 287]</ref><ref>[http://books.google.com/books?id=9gUjaCMlX5oC&pg=PA37&dq=dobsonian+amateur+telescope+makers&lr= Timothy Ferris "'''Seeing in the Dark'''" - Page 39]</ref>"<ref name=DobsonianTelescope>{{ cite web
|title=Dobsonian telescope, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=December 20,
|year=2013
|url=https://en.wikipedia.org/wiki/Dobsonian_telescope
|accessdate=2014-01-03 }}</ref>
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=[[Instruments/Telescopes/Schmidt|Schmidt telescopes]]=
[[Image:Schmidt telescope (PSF).svg|thumb|200px|right|The diagram illustrates the optical ray paths inside a Schmidt telescope. Credit: .]]
[[Image:Alfred-Jensch-Teleskop.jpg|thumb|200px|left|The 2 meter diameter (Alfred-Jensch-Telescope at the Karl Schwarzschild Observatory in Tautenburg, Thuringia, Germany, is the largest '''Schmidt camera''' in the world. Credit: .]]
At the top of this lecture/article is the Schmidt Telescope at the former Brorfelde Observatory. It is now used by amateur astronomers. The telescope from 1966 is still located in the same building in Brorfelde as originally. Today the telescope has a 77 cm mirror and a digital 2048x2048 pixel CCD-camera. Originally photographic film was used, and in the lower right part an engineer is showing the former film-box, which was then placed behind the locker at the center of the telescope (at the prime focus).

"A '''Schmidt camera''', also referred to as the '''Schmidt telescope''', is a catadioptric astrophotographic [optical] telescope designed to provide wide fields of view with limited aberrations."<ref name=SchmidtCamera>{{ cite web
|title=Schmidt camera, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=December 30,
|year=2013
|url=https://en.wikipedia.org/wiki/Schmidt_camera
|accessdate=2014-01-03 }}</ref>
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=[[Instruments/Telescopes/Maksutovs|Maksutov telescopes]]=
[[Image:Maksutov 150mm.jpg|right|thumb|200px|A 150mm aperture Maksutov–Cassegrain telescope is shown. Credit: .]]
[[Image:Maksutov spot cassegrain.png|right|thumb|200px|Light path in a typical "Gregory" or "spot" Maksutov–Cassegrain is diagrammed. Credit: .]]
(contracted; show full)|accessdate=2012-12-09 }}</ref>

At second lower left is the Evpatoria RT-70 radar telescope in the Ukraine.

At lower right is an artist's impression of the two radar satellites TerraSAR-X and TanDEM-X.
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=
[[Instruments/Interferometers/Radios|Radio interferometry]]=
[[Image:Interf diagram.gif|thumb|right|200px|The diagram shows a possible layout for an astronomical interferometer, with the mirrors laid out in a parabolic arrangement (similar to the shape of a conventional telescope mirror). Credit: .]]
(contracted; show full)closure phase]] to combine telescopes separated by thousands of kilometers to form a radio interferometer with the resolution which would be given by a single dish which was thousands of kilometers in diameter. ... Astronomical interferometers can produce higher [[w:Angular resolution|resolution]] astronomical images than any other type of telescope. At radio wavelengths image resolutions of a few micro-[[w:arcsecond|arcsecond]]s have been obtained”<ref name=AstronomicalInterferometer/>.
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=
[[Instruments/Telescopes/Superluminals|Superluminal telescopes]]=

"The Cherenkov telescopes do not actually detect the gamma rays directly but instead detect the flashes of visible light [Cherenkov radiation] produced when gamma rays are absorbed by the Earth's atmosphere.<ref name=Penston>{{ cite web
|author = Margaret J. Penston
|date = 14 August 2002
|url=http://www.pparc.ac.uk/frontiers/latest/feature.asp?article=14F1&style=feature
|title = The electromagnetic spectrum
|publisher = Particle Physics and Astronomy Research Council
|accessdate = 17 August 2006 }}</ref>"<ref name=Astronomy>{{ cite web
|title=Astronomy, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=July 19,
|year=2012
|url=http://en.wikipedia.org/wiki/Astronomy
|accessdate=2012-07-28 }}</ref>

=[[Instruments/Telescopes/Plasma objects|Plasma-object telescopes]]=
[[Image:HallThruster 2.jpg|thumb|2 kW Hall thruster is in operation as part of the Hall Thruster Experiment at the Princeton Plasma Physics Laboratory. Credit: [[w:User:Dstaack|Dstaack]].]]
[[Image:Xenon hall thruster.jpg|thumb|This is a xenon 6 kW Hall thruster in operation at the NASA Jet Propulsion Laboratory. Credit: NASA/JPL-Caltech.]]
(contracted; show full)|year=2013
|url=http://en.wikipedia.org/wiki/Hall_effect_thruster
|accessdate=2013-05-28 }}</ref>

While these thrusters are not plasma-object telescopes, they may serve to maneuver or slew a space telescope. As sources of blue light they mat serve as calibrated light sources.
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=
[[Instruments/Telescopes/Gaseous objects|Gaseous-object telescopes]]=
[[Image:Sun Gun.jpg|thumb|right|200px|This is an image of a Sun Gun Telescope. Credit: .]]
The "'''Sun Gun Telescope''' [is] designed so that large groups of people can view the [[Sun (star)|sun]] safely - in particular it was created as a way to encourage children to become interested in [[astronomy]].  With this safe and portable device, both amateur science enthusiasts and professionals alike can observe sun spots."<ref name=SunGunTelescope>{{ cite web
|title=Sun Gun Telescope, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=December 2,
|year=2013
|url=https://en.wikipedia.org/wiki/Sun_Gun_Telescope
|accessdate=2014-01-03 }}</ref>

The "Sun Gun [has] a 60mm dia. 900mm fl. optical tube which is mounted inside a 3" PVC which is in turn connected to a 20" plastic flower planter. A rear projection screen is ... mounted on the top of the flower planter. The entire Sun Gun can be made from items easily found at most local hardware stores. The scope itself is an inexpensive 60mm refractor available from many sources."<ref name=SunGunTelescope/>
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=[[Instruments/Telescopes/Liquid objects|Liquid-object telescopes]]=
[[Image:Liquid Mirror Telescope.jpg|thumb|right|This is a liquid mirror telescope. Credit: .]]
"'''Liquid mirror telescopes''' are telescopes with mirrors made with a reflective liquid. The most common liquid used is mercury, but other liquids will work as well (for example, low melting alloys of gallium). The container for the liquid is rotating so that the liquid assumes a paraboloidal shape. A paraboloidal shape is precisely the shape needed for the primary mirror of a telescope. The rotating liquid assumes the paraboloidal shape regardless of the container's shape. To reduce the amount of liquid metal needed, and thus weight, a rotating mercury mirror uses a container that is as close to the necessary parabolic shape as possible. Liquid mirrors can be a low cost alternative to conventional large telescopes. Compared to a solid glass mirror that must be cast, ground, and polished, a rotating liquid metal mirror is much less expensive to manufacture."<ref name=LiquidMirrorTelescope>{{ cite web
|title=Liquid mirror telescope, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=October 1,
|year=2013
|url=https://en.wikipedia.org/wiki/Liquid_mirror_telescope
|accessdate=2014-01-03 }}</ref>

A "telescope with a liquid metal mirror can only be used [as a] zenith telescope that looks straight up".<ref name=LiquidMirrorTelescope/>
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=[[Instruments/Telescopes/Hydrogens|Hydrogen telescopes]]=
[[Image:Solarborg.jpg|right|thumb|200px|Here is an example of an amateur solar telescope equipped with a hydrogen-alpha filter system. Credit: .]]
"In the field of [[amateur astronomy]] ... Amateurs use ... hydrogen-alpha filter systems".<ref name=SolarTelescope>{{ cite web
|title=Solar telescope, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=December 30,
|year=2013
|url=https://en.wikipedia.org/wiki/Solar_telescope
|accessdate=2014-01-03 }}</ref>
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=Alloys[[Chemicals/Alloys|Alloys]]=
[[Image:Cloudcroft Observatory.jpg|thumb|right|200px|The image shows the dome of the NASA Orbital Debris Observatory near Cloudcroft, New Mexico. Credit: NASA.]]
[[Image:CCD_Debris_Telescope.png|thumb|left|200px|This image shows the CCD Debris Telescope that is under the NODO dome. Credit: ]]
"The NASA-LMT was 3 m (9.8 ft) aperture liquid mirror telescope located in NODO's main dome. It consisted of a 3 m diameter parabolic dish that held 4 U.S. gallons (15 l) of a highly reflective liquid metal, mercury, spinning at a rate of 10 rpm, with sensors mounted above on a fixed structure. Due to the primary mirror's material, the NASA-LMT was configured as a zenith telescope. Using 20 narrowband filters, it cataloged space debris in Earth's orbit."<ref name=NASAOrbitalDebrisObservatory>{{ cite web
|title=NASA Orbital Debris Observatory, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=May 6,
|year=2013
|url=https://en.wikipedia.org/wiki/NASA_Orbital_Debris_Observatory
|accessdate=2014-01-03 }}</ref>

"The 32 cm (13 in) CCD Debris Telescope (CDT) was a portable Schmidt camera equipped with a 512×512 pixel charge-coupled device (CCD) sensor. It operated at NODO from October of 1997 until December of 2001, and was used to characterize debris at or near geosynchronous orbit."<ref name=NASAOrbitalDebrisObservatory/>
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=[[Rocks/Meteorites|Meteorites]]=
[[Image:Carancas Meteorite 2.jpg|thumb|right|200px|The image contains a 27.70 g fragment of the Carancas meteorite fall. The scale cube is 1 cm<sup>3</sup>. Credit: Meteorite Recon.]]
"On September 20, the X-Ray Laboratory at the Faculty of Geological Sciences, Mayor de San Andres University, [[w:La Paz, Bolivia|La Paz, Bolivia]], published a report of their analysis of a small sample of material recovered from the impact site. They detected iron, nickel, cobalt, and traces of iridium &mdash; elements characteristic of the elemental composition of meteorites. The quantitative proportions of silicon, aluminum, potassium, calcium, magnesium, and phosphorus are incompatible with rocks that are normally found at the surface of the Earth.<ref name=Blanco>Mario Blanco Cazas, [http://fcpn.umsa.bo/fcpn/app?service=external/PublicationDownload&sp=227 "Informe Laboratorio de Rayos X &mdash; FRX-DRX"] (in Spanish), Universidad Mayor de San Andres, Facultad de Ciencias Geologicas, Instituto de Investigaciones Geologicas y del Medio Ambiente, La Paz, Bolivia, September 20, 2007. Retrieved October 10, 2007.</ref>"<ref name=2007CarancasImpactEvent>{{ cite web
|title=2007 Carancas impact event, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=April 26,
|year=2013
|url=http://en.wikipedia.org/wiki/2007_Carancas_impact_event
|accessdate=2013-05-12 }}</ref>
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=Shelters[[Astronomy/Observatories/Shelters|Shelters]]=

"Telescope domes have a slit or other opening in the roof that can be opened during observing, and closed when the telescope is not in use. In most cases, the entire upper portion of the telescope dome can be rotated to allow the instrument to observe different sections of the night sky. Radio telescopes usually do not have domes."<ref name=Observatory>{{ cite web
|title=Observatory, In: ''Wikipedia''
|publisher=Wikimedia Foundation, Inc
|location=San Francisco, California
|month=January 26,
|year=2013
|url=http://en.wikipedia.org/wiki/Observatory
|accessdate=2013-02-05 }}</ref>

=Spectroscopy[[Radiation astronomy/Spectroscopy|Spectroscopy]]=

"'''Astronomical spectroscopy''' is the technique of [[w:spectroscopy|spectroscopy]] used in [[astronomy]]. The object of study is the [[w:electromagnetic spectrum|spectrum]] of [[w:electromagnetic radiation|electromagnetic radiation]], including visible light, which [[w:radiant energy|radiates]] from [[w:star|star]]s and other celestial objects.  Spectroscopy can be used to derive many properties of distant stars and galaxies, such as their chemical composition, but al(contracted; show full)[[Category:Original research]]
[[Category:Physics and Astronomy]]
[[Category:Research]]
[[Category:Resources last modified in February 2015]]
[[Category:Technology]]
{{experimental}}{{article}}{{lecture}}{{astronomy}}{{Materials science}}{{technology}}

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