Usuário:Danilo.mac/pages-meta-history
Primeiros 100.000 bytes do dump ptwiki-20131202-pages-meta-history1.xml.bz2
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<text xml:space="preserve">Ciência que estuda a posição, os movimentos e a constituição dos corpos celestes..
Verbetes associados:
* [[asteróide]]
* [[astro]]
* [[estrela]]
* [[planeta]]
* [[sol]]
* [[rotacao|rotação]]
* [[translacao|translação]]
Links externos:
* http://www.astrociencia.cjb.net
* http://www.astronomy.com
* http://www.astronomynow.com
* http://www.nrao.edu - National Radio Astronomy Observatory
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<text xml:space="preserve">Ciência que estuda a posição, os movimentos e a constituição dos corpos celestes..
Verbetes associados:
* [[asteróide]]
* [[astro]]
* [[estrela]]
* [[planeta]]
* [[sol]]
* [[rotacao|rotação]]
* [[translacao|translação]]
Links externos:
* http://www.astrociencia.cjb.net
* http://www.astronomy.com
* http://www.astronomynow.com
* http://www.nrao.edu - National Radio Astronomy Observatory
</text>
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<text xml:space="preserve">Ciência que estuda a posição, os movimentos e a constituição dos corpos celestes..
Verbetes associados:
* [[asteróide]]
* [[astro]]
* [[estrela]]
* [[planeta]]
* [[sol]]
* [[rotacao|rotação]]
* [[translacao|translação]]
Links externos:
* http://www.astrociencia.cjb.net
* http://www.astronomy.com
* http://www.astronomynow.com
* http://www.nrao.edu - National Radio Astronomy Observatory
[[ms:astronomi]][[ar:?????? ????? ????????? ????????]] [[bs:Astronomija i Astrofizika]] [[ca:Astronomia]] [[cs:Astronomie]] [[da:Astronomi]] [[de:Astronomie]] [[el:?????????? ??? ???????????]] [[en:Astronomy]] [[eo:Astroscienco]] [[es:Astronomía y astrofísica]] [[et:Astronoomia]] [[eu:Astronomia]] [[fi:Tähtitiede]] [[fr:Astronomie]] [[hr:Astronomija i Astrofizika]] [[hu:Asztronómia és asztrofizika]] [[ia:Astronomia]] [[it:Astronomia]] [[ja:???]] [[ko:???]] [[la:Astronomia]] [[lt:Astronomija]] [[nl:Astronomie]] [[no:Astronomi]] [[pl:Astronomia]] [[pt:Astronomia]] [[ro:Astronomie]] [[ru:??????????]] [[simple:Astronomy]] [[sl:Astronomija in astrofizika]] [[sr:??????????? ? ???????????]] [[sv:Astronomi]] [[zh-cn:???]] [[zh-tw:???]]</text>
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<text xml:space="preserve">Ciência que estuda a posição, os movimentos e a constituição dos corpos celestes..
Verbetes associados:
* [[asteróide]]
* [[astro]]
* [[estrela]]
* [[planeta]]
* [[sol]]
* [[rotacao|rotação]]
* [[translacao|translação]]
Links externos:
* http://www.astrociencia.cjb.net
* http://www.astronomy.com
* http://www.astronomynow.com
* http://www.nrao.edu - National Radio Astronomy Observatory
[[[ms:astronomi]] [[ar:&#1593;&#1616;&#1604;&#1618;&#1605;&#1615; &#1575;&#1604;&#1601;&#1604;&#1603; &#1608;&#1575;&#1604;&#1601;&#1610;&#1586;&#1610;&#1575;&#1569; &#1575;&#1604;&#1601;&#1604;&#1603;&#1610;&#1577;&#1615;]] [[bs:Astronomija i Astrofizika]] [[ca:Astronomia]] [[cs:Astronomie]] [[da:Astronomi]] [[de:Astronomie]] [[el:&#913;&#963;&#964;&#961;&#959;&#957;&#959;&#956;&#943;&#945; &#954;&#945;&#953; &#945;&#963;&#964;&#961;&#959;&#966;&#965;&#963;&#953;&#954;&#942;]] [[en:Astronomy]] [[eo:Astroscienco]] [[es:Astronomía y astrofísica]] [[et:Astronoomia]] [[eu:Astronomia]] [[fi:Tähtitiede]] [[fr:Astronomie]] [[hr:Astronomija i Astrofizika]] [[hu:Asztron&#243;mia &#233;s asztrofizika]] [[ia:Astronomia]] [[ja:&#22825;&#25991;&#23398;]] [[ko:&#52380;&#47928;&#54617;]] [[la:Astronomia]] [[lt:Astronomija]] [[pl:Astronomia]] [[pt:Astronomia]] [[ro:Astronomie]] [[ru:&#1040;&#1089;&#1090;&#1088;&#1086;&#1085;&#1086;&#1084;&#1080;&#1103;]] [[sl:Astronomija in astrofizika]] [[sv:Astronomi]] [[zh:&#22825;&#25991;&#23398;]]</text>
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<text xml:space="preserve">Ciência que estuda a posição, os movimentos e a constituição dos corpos celestes..
Verbetes associados:
* [[asteróide]]
* [[astro]]
* [[estrela]]
* [[planeta]]
* [[sol]]
* [[rotacao|rotação]]
* [[translacao|translação]]
Links externos:
* http://www.astrociencia.cjb.net
* http://www.astronomy.com
* http://www.astronomynow.com
* http://www.nrao.edu - National Radio Astronomy Observatory
[[[ms:astronomi]] [[ar:&#1593;&#1616;&#1604;&#1618;&#1605;&#1615; &#1575;&#1604;&#1601;&#1604;&#1603; &#1608;&#1575;&#1604;&#1601;&#1610;&#1586;&#1610;&#1575;&#1569; &#1575;&#1604;&#1601;&#1604;&#1603;&#1610;&#1577;&#1615;]] [[bs:Astronomija i Astrofizika]] [[ca:Astronomia]] [[cs:Astronomie]] [[da:Astronomi]] [[de:Astronomie]] [[el:&#913;&#963;&#964;&#961;&#959;&#957;&#959;&#956;&#943;&#945; &#954;&#945;&#953; &#945;&#963;&#964;&#961;&#959;&#966;&#965;&#963;&#953;&#954;&#942;]] [[en:Astronomy]] [[eo:Astroscienco]] [[es:Astronomía y astrofísica]] [[et:Astronoomia]] [[eu:Astronomia]] [[fi:Tähtitiede]] [[fr:Astronomie]] [[hr:Astronomija i Astrofizika]] [[hu:Asztron&#243;mia &#233;s asztrofizika]] [[ia:Astronomia]] [[ja:&#22825;&#25991;&#23398;]] [[ko:&#52380;&#47928;&#54617;]] [[la:Astronomia]] [[lt:Astronomija]] [[nl:Astronomie]] [[pl:Astronomia]] [[ro:Astronomie]] [[ru:&#1040;&#1089;&#1090;&#1088;&#1086;&#1085;&#1086;&#1084;&#1080;&#1103;]] [[sl:Astronomija in astrofizika]] [[sv:Astronomi]] [[zh:&#22825;&#25991;&#23398;]]</text>
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<text xml:space="preserve">Ciência que estuda a posição, os movimentos e a constituição dos corpos celestes..
Verbetes associados:
* [[asteróide]]
* [[astro]]
* [[estrela]]
* [[planeta]]
* [[sol]]
* [[rotacao|rotação]]
* [[translacao|translação]]
Links externos:
* http://www.astrociencia.cjb.net
* http://www.astronomy.com
* http://www.astronomynow.com
* http://www.nrao.edu - National Radio Astronomy Observatory
[
[[af:Sterrekunde en Astrofisika]]
[[ar:عِلْمُ الفلك والفيزياء الفلكيةُ]]
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[[ca:Astronomia]]
[[cs:Astronomie]]
[[da:Astronomi]]
[[de:Astronomie]]
[[en:Astronomy]]
[[eo:Astroscienco]]
[[es:Astronomía y astrofísica]]
[[et:Astronoomia]]
[[eu:Astronomia]]
[[fi:Tähtitiede]]
[[fr:Astronomie]]
[[gl:Astronomía]]
[[hr:Astronomija i Astrofizika]]
[[hu:Asztronómia és asztrofizika]]
[[ia:Astronomia]]
[[it:Astronomia]]
[[ja:天文学]]
[[ko:천문학]]
[[la:Astronomia]]
[[lt:Astronomija]]
[[ms:Astronomi]]
[[nl:Astronomie]]
[[no:Astronomi]]
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[[ro:Astronomie şi astrofizică]]
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[[sr:Астрономија и астрофизика]]
[[sv:Astronomi]]
[[ta:வானியல்]]
[[zh-cn:天文学]]
[[zh-tw:天文學]]</text>
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<text xml:space="preserve">'''Astronomy''', which [[etymology|etymologically]] means "''[[law]] of the [[star|stars]]''",(From [[Greek language|Greek]]): &#940;&#963;&#964;&#961;&#959;, + [[nomos|&#957;&#972;&#956;&#959;&#962;]]) is a [[science]] involving the [[observation]] and explanation of [[event]]s occurring outside [[Earth]] and its [[atmosphere]]. It studies the origins, evolution, physical and chemical properties of all the objects that can be observed in the sky
(and are outside the earth), as well as all the processes involving them.
What subfields it includes is a question whose answer has been changing with the ages. During part of the 20th century astronomy was considered to be separated in [[astrometry]], [[celestial mechanics]] and [[astrophysics]]. Of the three, astrophysics has gained certain preeminence, as that can be
seen reflected in the naming of the University departments
and institutions involved in astronomical research: the oldest ones are invariably ''Astronomy'' departments and institutes, the newest ones tend to include astrophysics in their names, sometimes excluding the word astronomy, to
emphasize the nature of its research. Furthermore, astrophysical research, specially in [[theoretical astrophysics]] can be carried out by people whose background is in physics or mathematics rather than astronomy.
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:moon.crater.arp.300pix.jpg]]<br><small>
'' '''Lunar astronomy:''' the far side of Earth's Moon. The large impact basin pictured is Crater 308. It spans about 30 kilometers (19 miles) and was photographed by the crew of Apollo 11 as they circled the Moon in 1969''<br>
[[media:moon.crater.arp.750pix.jpg|Larger version<br>]]<br>
</small>
</div>
Astronomy is one of the few sciences where [[amateur astronomy|amateurs]] still play an active role, especially in the discovery and monitoring of transient [[phenomena]]. Astronomy is not to be confused with [[astrology]], a [[pseudoscience]] which attempts to predict a person's destiny by tracking the paths of astronomical objects. Although the two fields share a common origin, they are quite different; astronomy embraces the [[scientific method]], while astrology, with no basis in science, does not.
==Divisions of astronomy==
Given its huge scope, astronomy is divided into different branches. A first main distinction is between ''theoretical'' and ''observational'' astronomy. ''Observers'' use a variety of means to obtain data about different phenomena, data that is then used by ''theorists'' to create and constrain theories and models, to explain observations and to predict new ones; observer and theorist are not necessarily different persons, and rather than two perfectly delimited fields, there is a continuum of scientists that put more or less emphasis in observation or theory.
Fields of study are also categorized in another two ways: by ''subject'', usually according to the region of space (e.g. Galactic astronomy) or ''problems addressed'' (such as star formation or cosmology); or by the way used for obtaining information
(essentially, what region of the [[electromagnetic spectrum]] is used). While the first division is applicable to both observers and theorist, the second one applies only to observers
(imperfectly), as theorists try to use all the information available, in all wavelength, and observers often
observe in more than one region of the spectrum.
===By subject or problem addressed===
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:dust.devil.mars.arp.300pix.jpg]]<br><small>
'' '''Planetary astronomy, or Planetary Sciences:''' a Martian dust devil. Photographed by the NASA Global Surveyor in Mars orbit, the long dark streak is formed by the movement of a swirling column of Martian atmosphere (with similarities to a terrestrial tornado). The dust devil (the black spot) is climbing the crater wall. Dust devils occur when the atmosphere is heated by a warm surface and begins to spin as it rises. The streaks in the right hand half of the picture are sand dunes on the crater floor.''<br>
[[media:dust.devil.mars.arp.750pix.jpg|Larger version<br>]]<br>
</small>
</div>
*[[Astrometry]]: Measures positions of objects in the sky and their changes.Necessary to define the system of coordinates used and the [[kinematics]] of object in our galaxy.
*[[Cosmology|Observational cosmology]]: Study of the universe as a whole and its evolution.
*[[Galactic astronomy]]: It used to be the study of the structure and components of our galaxy. Now includes study of other galaxies that can be observed in detail.
*[[Extragalactic astronomy]]: Study of objects (mainly galaxies) outside our galaxy.
*[[Galaxy formation and evolution]]: Study of the formation of the galaxies, and its evolution to the observed present state.
*[[Star formation]]: Study of the condition and processes that led to the formation of stars in the interior of gas clouds, and the process of formation itself.
*[[Stellar evolution]]: Study of the evolution of stars from its formation to its end as a stellar remnant.
*[[Stellar astronomy]]: Study of stars, in general.
See [[list of astronomical topics]] for a more exhaustive list of astronomy-related pages.
===By ways of obtaining information===
In astronomy, the main way of obtaining information is through
the detection and analysis of [[electromagnetic radiation]],
[[photon|photons]], but information is also carried by [[cosmic ray]]s, [[neutrino|neutrinos]], and, in the near future, [[gravitational wave|gravitational waves]] (see [[LIGO]] and [[LISA]]).
A traditional division of astronomy is given by the region of
the [[electromagnetic spectrum]] observed:
*[[Optical astronomy]] refers to the techniques used to detect and analyze [[light]] in and slightly around the [[wavelength]]s than can be detected with the [[eye]]s (about 400 - 800 nm). The most common tool is the [[telescope]], with [[electronic imager]]s and [[spectrograph]]s.
*[[Infrared astronomy]] deals with the detection of infrared radiation (wavelengths longer than red light). The most common tool is the [[telescope]] but with the instrument optimized for infrared. [[Space telescope]]s are also used to eliminate noise (electromagnetic interference) from the atmosphere.
*[[Radio astronomy]] uses completely different instruments to detect [[radiation]] of wavelengths of mm to cm. The receivers are similar to those used in [[radio]] broadcast transmission (which uses those wavelengths of radiation). See also [[Radio telescope]]s.
*[[High-energy astronomy]]
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:grav.lens1.arp.300pix.jpg]]<br><small>
'' '''Extragalactic astronomy''': gravitational lensing. This Hubble Space Telescope image shows several blue, loop-shaped objects that actually are multiple images of the same galaxy. They have been duplicated by the gravitational lens effect of the cluster of yellow, elliptical and spiral galaxies near the photograph's center. The gravitational lens is produced by the cluster's tremendous gravitational field that bends light to magnify, brighten and distort the image of a more distant object.'' <br>'''Click on the picture for more information and a larger version.'''
</small>
</div>
Optical and radio astronomy can be performed with ground-based [[observatory|observatories]], because the [[Earth's atmosphere|atmosphere]] is transparent at those wavelengths. Infrared light is heavily absorbed by
[[water vapor]], so infrared observatories have to be located in high, dry places or in space.
The atmosphere is opaque at the wavelengths used by [[X-ray astronomy]], [[gamma-ray astronomy]], [[UV astronomy]] and, except for a few wavelength "windows", [[Far infrared astronomy]] , and so observations
can be carried out only from [[balloon]]s or [[space observatory|space observatories]].
==Short history==
In the early part of its history, astronomy involved only the observation and predictions of the motions of the objects in the sky that could be seen with the naked eye. The [[Rigveda]] refers to the 27 [[constellations]] associated with the motions of the sun and also the 12 [[Zodiac|zodiacal]] divisions of the sky. The [[Hellenic civilization|ancient Greeks]] made important contributions to astronomy, among them the definition of the [[apparent magnitude|magnitude]] system. The [[Bible]] contains a number of statements on the position of the earth in the universe and the nature of the stars and planets, most of which are poetic rather than literal; see [[Biblical cosmology]]. In [[500|500 AD]], [[Aryabhata]] presented a mathematical system that took the earth to spin on its axis and considered the motions of the planets with respect to the sun.
The study of astronomy almost stopped during the middle ages, except for
the work of [[Arab|Arabic]] astronomers. In the late 9th century the Islamic astronomer al-Farghani (Abu'l-Abbas Ahmad ibn Muhammad ibn Kathir al-Farghani) wrote extensively on the motion of celestial bodies. In the 12th century, his works were translated into Latin, and it is said that Dante got his astronomical knowledge from al-Farghani's books.
In the late [[10th century]], a huge [[observatory]] was built near [[Tehran]], [[Iran]], by the astronomer al-Khujandi who observed a series of meridian transits of the Sun, which allowed him to calculate the obliquity of the ecliptic, also known as the tilt of the Earth's axis relative to the Sun. As we know today, the Earth's tilt is approximately 23&deg;34', and al-Khujandi measured it as being 23&deg;32'19". Using this information, he also compiled a list of [[latitude]]s and [[longitude]]s of major cities.
[[Omar Khayyam]] (Ghiyath al-Din Abu'l-Fath Umar ibn Ibrahim al-Nisaburi al-Khayyami) was a great [[Persia]]n scientist, philosopher, and poet who lived from [[1048]]-[[1131]]. He compiled many astronomical tables and performed a reformation of the [[calendar]] which was more accurate than the [[Julian Calendar|Julian]] and came close to the [[Gregorian calendar|Gregorian]]. An amazing feat was his calculation of the year to be 365.24219858156 days long, which is accurate to the 6th decimal place.
During the [[renaissance]] [[Copernicus]] proposed a [[heliocentric model]] of the [[Solar System]]. His work was defended, expanded upon, and corrected by [[Galileo Galilei]] and [[Johannes Kepler]]. Kepler was the first to devise a system which described correctly the details of the motion of the planets with the Sun at the center. However, Kepler did not understand the reasons behind the laws he wrote down. It was left to [[Sir Isaac Newton|Newton's]] invention of [[celestial dynamics]] and his [[law of gravitation]] to finally explain the motions of the [[planet]]s.
Stars were found to be far away objects. With the advent of [[spectroscopy]] it was proved that they were similar to our own sun, but with a wide range of [[temperature]]s, [[mass]]es and sizes. The existence of our [[galaxy]], the [[Milky Way]], as a separate group of stars was only proven in the 20th century, along with the existence of "external" galaxies, and soon after, the expansion of the [[universe]] seen in the recession of most galaxies from us. [[Cosmology]] made huge advances during the 20th century, with the model of the [[big bang]] heavily supported by the evidence provided by astronomy and physics, such as the [[cosmic microwave background radiation]], [[Hubble's Law]] and [[big bang nucleosynthesis|cosmological abundances of elements]].
For a more detailed history of astronomy, see the [[history of astronomy]].
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:ant.nebula.arp.300pix.jpg]]<br><small>
'' '''Stellar astronomy,Stellar evolution:''' The Ant planetary nebula. The ejection of gas, from the dying star at the center, has intriguing symmetrical patterns unlike the chaotic patterns expected from an ordinary explosion. Scientists using Hubble would like to understand how a spherical star can produce such prominent symmetries in the gas that it ejects.''<br>
'''Click on the picture for more information and a larger version.'''
</small>
</div>
== See also ==
* [[Astronomer|Astronomers and Astrophysicists]]
* [[space science]]...
* [[Timeline of black hole physics]]
* [[Timeline of cosmology]]
* [[Timeline of cosmic microwave background astronomy]]
* [[Timeline of other background radiation fields]]
* [[Timeline of galaxies, clusters of galaxies, and large scale structure]]
* [[Timeline of the interstellar medium and intergalactic medium]]
* [[Timeline of white dwarfs, neutron stars, and supernovae]]
* [[Timeline of stellar astronomy]]
* [[Timeline of solar astronomy]]
* [[Timeline of solar system astronomy]]
* [[Timeline of astronomical maps, catalogs, and surveys]]
* [[Timeline of telescopes, observatories, and observing technology]]
* [[Timeline of artificial satellites and space probes]]
*[[International Astronomical Union]]
*[[American Astronomical Society]]
*[[Royal Astronomical Society]]
*[[European Southern Observatory]]
==Astronomy Tools==
http://www.asimpleclick.com/nasa_related.htm for additional info
* [[Telescope]]
* [[Computers]]
* [[Calculator]]
* [[Observatory]]
* [[Space observatory]]
==External links==
===Organizations===
*[http://www.aavso.org/ American Association of Variable Star Observers]
*[http://www.drastronomy.com/ Durham Region Astronomical Association]
*[http://www.noao.edu/ National Optical Astronomy Observatories]
*[http://www.nyaa-starfest.com/ North York Astronomical Association]
*[http://www.rasc.ca/ Royal Astronomical Society of Canada]
*[http://www.ras.org.uk/ Royal Astronomical Society (UK)]
*[http://www.astro.cz/ Czech Astronomical Society]
*[http://www.hia-iha.nrc-cnrc.gc.ca/ Herzberg Institute of Astrophysics]
*[http://www.slasonline.org/ Saint Louis Astronomical Society]
===References===
* [http://www.ency-astro.com/ Encyclopedia of Astronomy and Astrophysics]
* [http://xxx.lanl.gov/ Los Alamos Astrophysics e-Print Database]
* [http://antwrp.gsfc.nasa.gov/apod/ Astronomy Picture of the Day]
* [http://www.phys-astro.sonoma.edu/BruceMedalists/ 20th Century Astronomers]
*[http://physics.unr.edu/grad/welser/astro/arab.html Islamic and Arab Astronomy]
[[af:Sterrekunde en Astrofisika]]
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<text xml:space="preserve">'''Astronomy''', which [[etymology|etymologically]] means "''[[law]] of the [[star|stars]]''",(From [[Greek language|Greek]]): &#940;&#963;&#964;&#961;&#959;, + [[nomos|&#957;&#972;&#956;&#959;&#962;]]) is a [[science]] involving the [[observation]] and explanation of [[event]]s occurring outside [[Earth]] and its [[atmosphere]]. It studies the origins, evolution, physical and chemical properties of all the objects that can be observed in the sky
(and are outside the earth), as well as all the processes involving them.
What subfields it includes is a question whose answer has been changing with the ages. During part of the 20th century astronomy was considered to be separated in [[astrometry]], [[celestial mechanics]] and [[astrophysics]]. Of the three, astrophysics has gained certain preeminence, as that can be
seen reflected in the naming of the University departments
and institutions involved in astronomical research: the oldest ones are invariably ''Astronomy'' departments and institutes, the newest ones tend to include astrophysics in their names, sometimes excluding the word astronomy, to
emphasize the nature of its research. Furthermore, astrophysical research, specially in [[theoretical astrophysics]] can be carried out by people whose background is in physics or mathematics rather than astronomy.
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[imagem:moon.crater.arp.300pix.jpg]]<br><small>
'' '''Lunar astronomy:''' the far side of Earth's Moon. The large impact basin pictured is Crater 308. It spans about 30 kilometers (19 miles) and was photographed by the crew of Apollo 11 as they circled the Moon in 1969''<br>
[[media:moon.crater.arp.750pix.jpg|Larger version<br>]]<br>
</small>
</div>
Astronomy is one of the few sciences where [[amateur astronomy|amateurs]] still play an active role, especially in the discovery and monitoring of transient [[phenomena]]. Astronomy is not to be confused with [[astrology]], a [[pseudoscience]] which attempts to predict a person's destiny by tracking the paths of astronomical objects. Although the two fields share a common origin, they are quite different; astronomy embraces the [[scientific method]], while astrology, with no basis in science, does not.
==Divisions of astronomy==
Given its huge scope, astronomy is divided into different branches. A first main distinction is between ''theoretical'' and ''observational'' astronomy. ''Observers'' use a variety of means to obtain data about different phenomena, data that is then used by ''theorists'' to create and constrain theories and models, to explain observations and to predict new ones; observer and theorist are not necessarily different persons, and rather than two perfectly delimited fields, there is a continuum of scientists that put more or less emphasis in observation or theory.
Fields of study are also categorized in another two ways: by ''subject'', usually according to the region of space (e.g. Galactic astronomy) or ''problems addressed'' (such as star formation or cosmology); or by the way used for obtaining information
(essentially, what region of the [[electromagnetic spectrum]] is used). While the first division is applicable to both observers and theorist, the second one applies only to observers
(imperfectly), as theorists try to use all the information available, in all wavelength, and observers often
observe in more than one region of the spectrum.
===By subject or problem addressed===
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:dust.devil.mars.arp.300pix.jpg]]<br><small>
'' '''Planetary astronomy, or Planetary Sciences:''' a Martian dust devil. Photographed by the NASA Global Surveyor in Mars orbit, the long dark streak is formed by the movement of a swirling column of Martian atmosphere (with similarities to a terrestrial tornado). The dust devil (the black spot) is climbing the crater wall. Dust devils occur when the atmosphere is heated by a warm surface and begins to spin as it rises. The streaks in the right hand half of the picture are sand dunes on the crater floor.''<br>
[[media:dust.devil.mars.arp.750pix.jpg|Larger version<br>]]<br>
</small>
</div>
*[[Astrometry]]: Measures positions of objects in the sky and their changes.Necessary to define the system of coordinates used and the [[kinematics]] of object in our galaxy.
*[[Cosmology|Observational cosmology]]: Study of the universe as a whole and its evolution.
*[[Galactic astronomy]]: It used to be the study of the structure and components of our galaxy. Now includes study of other galaxies that can be observed in detail.
*[[Extragalactic astronomy]]: Study of objects (mainly galaxies) outside our galaxy.
*[[Galaxy formation and evolution]]: Study of the formation of the galaxies, and its evolution to the observed present state.
*[[Star formation]]: Study of the condition and processes that led to the formation of stars in the interior of gas clouds, and the process of formation itself.
*[[Stellar evolution]]: Study of the evolution of stars from its formation to its end as a stellar remnant.
*[[Stellar astronomy]]: Study of stars, in general.
See [[list of astronomical topics]] for a more exhaustive list of astronomy-related pages.
===By ways of obtaining information===
In astronomy, the main way of obtaining information is through
the detection and analysis of [[electromagnetic radiation]],
[[photon|photons]], but information is also carried by [[cosmic ray]]s, [[neutrino|neutrinos]], and, in the near future, [[gravitational wave|gravitational waves]] (see [[LIGO]] and [[LISA]]).
A traditional division of astronomy is given by the region of
the [[electromagnetic spectrum]] observed:
*[[Optical astronomy]] refers to the techniques used to detect and analyze [[light]] in and slightly around the [[wavelength]]s than can be detected with the [[eye]]s (about 400 - 800 nm). The most common tool is the [[telescope]], with [[electronic imager]]s and [[spectrograph]]s.
*[[Infrared astronomy]] deals with the detection of infrared radiation (wavelengths longer than red light). The most common tool is the [[telescope]] but with the instrument optimized for infrared. [[Space telescope]]s are also used to eliminate noise (electromagnetic interference) from the atmosphere.
*[[Radio astronomy]] uses completely different instruments to detect [[radiation]] of wavelengths of mm to cm. The receivers are similar to those used in [[radio]] broadcast transmission (which uses those wavelengths of radiation). See also [[Radio telescope]]s.
*[[High-energy astronomy]]
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:grav.lens1.arp.300pix.jpg]]<br><small>
'' '''Extragalactic astronomy''': gravitational lensing. This Hubble Space Telescope image shows several blue, loop-shaped objects that actually are multiple images of the same galaxy. They have been duplicated by the gravitational lens effect of the cluster of yellow, elliptical and spiral galaxies near the photograph's center. The gravitational lens is produced by the cluster's tremendous gravitational field that bends light to magnify, brighten and distort the image of a more distant object.'' <br>'''Click on the picture for more information and a larger version.'''
</small>
</div>
Optical and radio astronomy can be performed with ground-based [[observatory|observatories]], because the [[Earth's atmosphere|atmosphere]] is transparent at those wavelengths. Infrared light is heavily absorbed by
[[water vapor]], so infrared observatories have to be located in high, dry places or in space.
The atmosphere is opaque at the wavelengths used by [[X-ray astronomy]], [[gamma-ray astronomy]], [[UV astronomy]] and, except for a few wavelength "windows", [[Far infrared astronomy]] , and so observations
can be carried out only from [[balloon]]s or [[space observatory|space observatories]].
==Short history==
In the early part of its history, astronomy involved only the observation and predictions of the motions of the objects in the sky that could be seen with the naked eye. The [[Rigveda]] refers to the 27 [[constellations]] associated with the motions of the sun and also the 12 [[Zodiac|zodiacal]] divisions of the sky. The [[Hellenic civilization|ancient Greeks]] made important contributions to astronomy, among them the definition of the [[apparent magnitude|magnitude]] system. The [[Bible]] contains a number of statements on the position of the earth in the universe and the nature of the stars and planets, most of which are poetic rather than literal; see [[Biblical cosmology]]. In [[500|500 AD]], [[Aryabhata]] presented a mathematical system that took the earth to spin on its axis and considered the motions of the planets with respect to the sun.
The study of astronomy almost stopped during the middle ages, except for
the work of [[Arab|Arabic]] astronomers. In the late 9th century the Islamic astronomer al-Farghani (Abu'l-Abbas Ahmad ibn Muhammad ibn Kathir al-Farghani) wrote extensively on the motion of celestial bodies. In the 12th century, his works were translated into Latin, and it is said that Dante got his astronomical knowledge from al-Farghani's books.
In the late [[10th century]], a huge [[observatory]] was built near [[Tehran]], [[Iran]], by the astronomer al-Khujandi who observed a series of meridian transits of the Sun, which allowed him to calculate the obliquity of the ecliptic, also known as the tilt of the Earth's axis relative to the Sun. As we know today, the Earth's tilt is approximately 23&deg;34', and al-Khujandi measured it as being 23&deg;32'19". Using this information, he also compiled a list of [[latitude]]s and [[longitude]]s of major cities.
[[Omar Khayyam]] (Ghiyath al-Din Abu'l-Fath Umar ibn Ibrahim al-Nisaburi al-Khayyami) was a great [[Persia]]n scientist, philosopher, and poet who lived from [[1048]]-[[1131]]. He compiled many astronomical tables and performed a reformation of the [[calendar]] which was more accurate than the [[Julian Calendar|Julian]] and came close to the [[Gregorian calendar|Gregorian]]. An amazing feat was his calculation of the year to be 365.24219858156 days long, which is accurate to the 6th decimal place.
During the [[renaissance]] [[Copernicus]] proposed a [[heliocentric model]] of the [[Solar System]]. His work was defended, expanded upon, and corrected by [[Galileo Galilei]] and [[Johannes Kepler]]. Kepler was the first to devise a system which described correctly the details of the motion of the planets with the Sun at the center. However, Kepler did not understand the reasons behind the laws he wrote down. It was left to [[Sir Isaac Newton|Newton's]] invention of [[celestial dynamics]] and his [[law of gravitation]] to finally explain the motions of the [[planet]]s.
Stars were found to be far away objects. With the advent of [[spectroscopy]] it was proved that they were similar to our own sun, but with a wide range of [[temperature]]s, [[mass]]es and sizes. The existence of our [[galaxy]], the [[Milky Way]], as a separate group of stars was only proven in the 20th century, along with the existence of "external" galaxies, and soon after, the expansion of the [[universe]] seen in the recession of most galaxies from us. [[Cosmology]] made huge advances during the 20th century, with the model of the [[big bang]] heavily supported by the evidence provided by astronomy and physics, such as the [[cosmic microwave background radiation]], [[Hubble's Law]] and [[big bang nucleosynthesis|cosmological abundances of elements]].
For a more detailed history of astronomy, see the [[history of astronomy]].
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:ant.nebula.arp.300pix.jpg]]<br><small>
'' '''Stellar astronomy,Stellar evolution:''' The Ant planetary nebula. The ejection of gas, from the dying star at the center, has intriguing symmetrical patterns unlike the chaotic patterns expected from an ordinary explosion. Scientists using Hubble would like to understand how a spherical star can produce such prominent symmetries in the gas that it ejects.''<br>
'''Click on the picture for more information and a larger version.'''
</small>
</div>
== See also ==
* [[Astronomer|Astronomers and Astrophysicists]]
* [[space science]]...
* [[Timeline of black hole physics]]
* [[Timeline of cosmology]]
* [[Timeline of cosmic microwave background astronomy]]
* [[Timeline of other background radiation fields]]
* [[Timeline of galaxies, clusters of galaxies, and large scale structure]]
* [[Timeline of the interstellar medium and intergalactic medium]]
* [[Timeline of white dwarfs, neutron stars, and supernovae]]
* [[Timeline of stellar astronomy]]
* [[Timeline of solar astronomy]]
* [[Timeline of solar system astronomy]]
* [[Timeline of astronomical maps, catalogs, and surveys]]
* [[Timeline of telescopes, observatories, and observing technology]]
* [[Timeline of artificial satellites and space probes]]
*[[International Astronomical Union]]
*[[American Astronomical Society]]
*[[Royal Astronomical Society]]
*[[European Southern Observatory]]
==Astronomy Tools==
http://www.asimpleclick.com/nasa_related.htm for additional info
* [[Telescope]]
* [[Computers]]
* [[Calculator]]
* [[Observatory]]
* [[Space observatory]]
==External links==
===Organizations===
*[http://www.aavso.org/ American Association of Variable Star Observers]
*[http://www.drastronomy.com/ Durham Region Astronomical Association]
*[http://www.noao.edu/ National Optical Astronomy Observatories]
*[http://www.nyaa-starfest.com/ North York Astronomical Association]
*[http://www.rasc.ca/ Royal Astronomical Society of Canada]
*[http://www.ras.org.uk/ Royal Astronomical Society (UK)]
*[http://www.astro.cz/ Czech Astronomical Society]
*[http://www.hia-iha.nrc-cnrc.gc.ca/ Herzberg Institute of Astrophysics]
*[http://www.slasonline.org/ Saint Louis Astronomical Society]
===References===
* [http://www.ency-astro.com/ Encyclopedia of Astronomy and Astrophysics]
* [http://xxx.lanl.gov/ Los Alamos Astrophysics e-Print Database]
* [http://antwrp.gsfc.nasa.gov/apod/ Astronomy Picture of the Day]
* [http://www.phys-astro.sonoma.edu/BruceMedalists/ 20th Century Astronomers]
*[http://physics.unr.edu/grad/welser/astro/arab.html Islamic and Arab Astronomy]
[[af:Sterrekunde en Astrofisika]]
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<text xml:space="preserve">'''Astronomia''', que [[etimologia|etimologicamente]] significa "''[[lei]] das [[estrela]]s''",(do [[Grego]]): &#940;&#963;&#964;&#961;&#959;, + [[nomos|&#957;&#972;&#956;&#959;&#962;]]) é uma [[ciência]] que envolve a [[observação]] and explicação de [[evento]]s que ocorrem fora da [[Terra]] e de sua [[atmosfera]]. Estuda as origens, evolução e propriedades físicas e químicas de todos os objectos que podem ser observados no céu (e estão além da Terra), bem como todos os processos que os involvem.
What subfields it includes is a question whose answer has been changing with the ages. During part of the 20th century astronomy was considered to be separated in [[astrometry]], [[celestial mechanics]] and [[astrophysics]]. Of the three, astrophysics has gained certain preeminence, as that can be
seen reflected in the naming of the University departments
and institutions involved in astronomical research: the oldest ones are invariably ''Astronomy'' departments and institutes, the newest ones tend to include astrophysics in their names, sometimes excluding the word astronomy, to
emphasize the nature of its research. Furthermore, astrophysical research, specially in [[theoretical astrophysics]] can be carried out by people whose background is in physics or mathematics rather than astronomy.
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[imagem:moon.crater.arp.300pix.jpg]]<br><small>
'' '''Lunar astronomy:''' the far side of Earth's Moon. The large impact basin pictured is Crater 308. It spans about 30 kilometers (19 miles) and was photographed by the crew of Apollo 11 as they circled the Moon in 1969''<br>
[[media:moon.crater.arp.750pix.jpg|Larger version<br>]]<br>
</small>
</div>
Astronomy is one of the few sciences where [[amateur astronomy|amateurs]] still play an active role, especially in the discovery and monitoring of transient [[phenomena]]. Astronomy is not to be confused with [[astrology]], a [[pseudoscience]] which attempts to predict a person's destiny by tracking the paths of astronomical objects. Although the two fields share a common origin, they are quite different; astronomy embraces the [[scientific method]], while astrology, with no basis in science, does not.
==Divisions of astronomy==
Given its huge scope, astronomy is divided into different branches. A first main distinction is between ''theoretical'' and ''observational'' astronomy. ''Observers'' use a variety of means to obtain data about different phenomena, data that is then used by ''theorists'' to create and constrain theories and models, to explain observations and to predict new ones; observer and theorist are not necessarily different persons, and rather than two perfectly delimited fields, there is a continuum of scientists that put more or less emphasis in observation or theory.
Fields of study are also categorized in another two ways: by ''subject'', usually according to the region of space (e.g. Galactic astronomy) or ''problems addressed'' (such as star formation or cosmology); or by the way used for obtaining information
(essentially, what region of the [[electromagnetic spectrum]] is used). While the first division is applicable to both observers and theorist, the second one applies only to observers
(imperfectly), as theorists try to use all the information available, in all wavelength, and observers often
observe in more than one region of the spectrum.
===By subject or problem addressed===
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:dust.devil.mars.arp.300pix.jpg]]<br><small>
'' '''Planetary astronomy, or Planetary Sciences:''' a Martian dust devil. Photographed by the NASA Global Surveyor in Mars orbit, the long dark streak is formed by the movement of a swirling column of Martian atmosphere (with similarities to a terrestrial tornado). The dust devil (the black spot) is climbing the crater wall. Dust devils occur when the atmosphere is heated by a warm surface and begins to spin as it rises. The streaks in the right hand half of the picture are sand dunes on the crater floor.''<br>
[[media:dust.devil.mars.arp.750pix.jpg|Larger version<br>]]<br>
</small>
</div>
*[[Astrometry]]: Measures positions of objects in the sky and their changes.Necessary to define the system of coordinates used and the [[kinematics]] of object in our galaxy.
*[[Cosmology|Observational cosmology]]: Study of the universe as a whole and its evolution.
*[[Galactic astronomy]]: It used to be the study of the structure and components of our galaxy. Now includes study of other galaxies that can be observed in detail.
*[[Extragalactic astronomy]]: Study of objects (mainly galaxies) outside our galaxy.
*[[Galaxy formation and evolution]]: Study of the formation of the galaxies, and its evolution to the observed present state.
*[[Star formation]]: Study of the condition and processes that led to the formation of stars in the interior of gas clouds, and the process of formation itself.
*[[Stellar evolution]]: Study of the evolution of stars from its formation to its end as a stellar remnant.
*[[Stellar astronomy]]: Study of stars, in general.
See [[list of astronomical topics]] for a more exhaustive list of astronomy-related pages.
===By ways of obtaining information===
In astronomy, the main way of obtaining information is through
the detection and analysis of [[electromagnetic radiation]],
[[photon|photons]], but information is also carried by [[cosmic ray]]s, [[neutrino|neutrinos]], and, in the near future, [[gravitational wave|gravitational waves]] (see [[LIGO]] and [[LISA]]).
A traditional division of astronomy is given by the region of
the [[electromagnetic spectrum]] observed:
*[[Optical astronomy]] refers to the techniques used to detect and analyze [[light]] in and slightly around the [[wavelength]]s than can be detected with the [[eye]]s (about 400 - 800 nm). The most common tool is the [[telescope]], with [[electronic imager]]s and [[spectrograph]]s.
*[[Infrared astronomy]] deals with the detection of infrared radiation (wavelengths longer than red light). The most common tool is the [[telescope]] but with the instrument optimized for infrared. [[Space telescope]]s are also used to eliminate noise (electromagnetic interference) from the atmosphere.
*[[Radio astronomy]] uses completely different instruments to detect [[radiation]] of wavelengths of mm to cm. The receivers are similar to those used in [[radio]] broadcast transmission (which uses those wavelengths of radiation). See also [[Radio telescope]]s.
*[[High-energy astronomy]]
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:grav.lens1.arp.300pix.jpg]]<br><small>
'' '''Extragalactic astronomy''': gravitational lensing. This Hubble Space Telescope image shows several blue, loop-shaped objects that actually are multiple images of the same galaxy. They have been duplicated by the gravitational lens effect of the cluster of yellow, elliptical and spiral galaxies near the photograph's center. The gravitational lens is produced by the cluster's tremendous gravitational field that bends light to magnify, brighten and distort the image of a more distant object.'' <br>'''Click on the picture for more information and a larger version.'''
</small>
</div>
Optical and radio astronomy can be performed with ground-based [[observatory|observatories]], because the [[Earth's atmosphere|atmosphere]] is transparent at those wavelengths. Infrared light is heavily absorbed by
[[water vapor]], so infrared observatories have to be located in high, dry places or in space.
The atmosphere is opaque at the wavelengths used by [[X-ray astronomy]], [[gamma-ray astronomy]], [[UV astronomy]] and, except for a few wavelength "windows", [[Far infrared astronomy]] , and so observations
can be carried out only from [[balloon]]s or [[space observatory|space observatories]].
==Short history==
In the early part of its history, astronomy involved only the observation and predictions of the motions of the objects in the sky that could be seen with the naked eye. The [[Rigveda]] refers to the 27 [[constellations]] associated with the motions of the sun and also the 12 [[Zodiac|zodiacal]] divisions of the sky. The [[Hellenic civilization|ancient Greeks]] made important contributions to astronomy, among them the definition of the [[apparent magnitude|magnitude]] system. The [[Bible]] contains a number of statements on the position of the earth in the universe and the nature of the stars and planets, most of which are poetic rather than literal; see [[Biblical cosmology]]. In [[500|500 AD]], [[Aryabhata]] presented a mathematical system that took the earth to spin on its axis and considered the motions of the planets with respect to the sun.
The study of astronomy almost stopped during the middle ages, except for
the work of [[Arab|Arabic]] astronomers. In the late 9th century the Islamic astronomer al-Farghani (Abu'l-Abbas Ahmad ibn Muhammad ibn Kathir al-Farghani) wrote extensively on the motion of celestial bodies. In the 12th century, his works were translated into Latin, and it is said that Dante got his astronomical knowledge from al-Farghani's books.
In the late [[10th century]], a huge [[observatory]] was built near [[Tehran]], [[Iran]], by the astronomer al-Khujandi who observed a series of meridian transits of the Sun, which allowed him to calculate the obliquity of the ecliptic, also known as the tilt of the Earth's axis relative to the Sun. As we know today, the Earth's tilt is approximately 23&deg;34', and al-Khujandi measured it as being 23&deg;32'19". Using this information, he also compiled a list of [[latitude]]s and [[longitude]]s of major cities.
[[Omar Khayyam]] (Ghiyath al-Din Abu'l-Fath Umar ibn Ibrahim al-Nisaburi al-Khayyami) was a great [[Persia]]n scientist, philosopher, and poet who lived from [[1048]]-[[1131]]. He compiled many astronomical tables and performed a reformation of the [[calendar]] which was more accurate than the [[Julian Calendar|Julian]] and came close to the [[Gregorian calendar|Gregorian]]. An amazing feat was his calculation of the year to be 365.24219858156 days long, which is accurate to the 6th decimal place.
During the [[renaissance]] [[Copernicus]] proposed a [[heliocentric model]] of the [[Solar System]]. His work was defended, expanded upon, and corrected by [[Galileo Galilei]] and [[Johannes Kepler]]. Kepler was the first to devise a system which described correctly the details of the motion of the planets with the Sun at the center. However, Kepler did not understand the reasons behind the laws he wrote down. It was left to [[Sir Isaac Newton|Newton's]] invention of [[celestial dynamics]] and his [[law of gravitation]] to finally explain the motions of the [[planet]]s.
Stars were found to be far away objects. With the advent of [[spectroscopy]] it was proved that they were similar to our own sun, but with a wide range of [[temperature]]s, [[mass]]es and sizes. The existence of our [[galaxy]], the [[Milky Way]], as a separate group of stars was only proven in the 20th century, along with the existence of "external" galaxies, and soon after, the expansion of the [[universe]] seen in the recession of most galaxies from us. [[Cosmology]] made huge advances during the 20th century, with the model of the [[big bang]] heavily supported by the evidence provided by astronomy and physics, such as the [[cosmic microwave background radiation]], [[Hubble's Law]] and [[big bang nucleosynthesis|cosmological abundances of elements]].
For a more detailed history of astronomy, see the [[history of astronomy]].
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:ant.nebula.arp.300pix.jpg]]<br><small>
'' '''Stellar astronomy,Stellar evolution:''' The Ant planetary nebula. The ejection of gas, from the dying star at the center, has intriguing symmetrical patterns unlike the chaotic patterns expected from an ordinary explosion. Scientists using Hubble would like to understand how a spherical star can produce such prominent symmetries in the gas that it ejects.''<br>
'''Click on the picture for more information and a larger version.'''
</small>
</div>
== See also ==
* [[Astronomer|Astronomers and Astrophysicists]]
* [[space science]]...
* [[Timeline of black hole physics]]
* [[Timeline of cosmology]]
* [[Timeline of cosmic microwave background astronomy]]
* [[Timeline of other background radiation fields]]
* [[Timeline of galaxies, clusters of galaxies, and large scale structure]]
* [[Timeline of the interstellar medium and intergalactic medium]]
* [[Timeline of white dwarfs, neutron stars, and supernovae]]
* [[Timeline of stellar astronomy]]
* [[Timeline of solar astronomy]]
* [[Timeline of solar system astronomy]]
* [[Timeline of astronomical maps, catalogs, and surveys]]
* [[Timeline of telescopes, observatories, and observing technology]]
* [[Timeline of artificial satellites and space probes]]
*[[International Astronomical Union]]
*[[American Astronomical Society]]
*[[Royal Astronomical Society]]
*[[European Southern Observatory]]
==Astronomy Tools==
http://www.asimpleclick.com/nasa_related.htm for additional info
* [[Telescope]]
* [[Computers]]
* [[Calculator]]
* [[Observatory]]
* [[Space observatory]]
==External links==
===Organizations===
*[http://www.aavso.org/ American Association of Variable Star Observers]
*[http://www.drastronomy.com/ Durham Region Astronomical Association]
*[http://www.noao.edu/ National Optical Astronomy Observatories]
*[http://www.nyaa-starfest.com/ North York Astronomical Association]
*[http://www.rasc.ca/ Royal Astronomical Society of Canada]
*[http://www.ras.org.uk/ Royal Astronomical Society (UK)]
*[http://www.astro.cz/ Czech Astronomical Society]
*[http://www.hia-iha.nrc-cnrc.gc.ca/ Herzberg Institute of Astrophysics]
*[http://www.slasonline.org/ Saint Louis Astronomical Society]
===References===
* [http://www.ency-astro.com/ Encyclopedia of Astronomy and Astrophysics]
* [http://xxx.lanl.gov/ Los Alamos Astrophysics e-Print Database]
* [http://antwrp.gsfc.nasa.gov/apod/ Astronomy Picture of the Day]
* [http://www.phys-astro.sonoma.edu/BruceMedalists/ 20th Century Astronomers]
*[http://physics.unr.edu/grad/welser/astro/arab.html Islamic and Arab Astronomy]
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<text xml:space="preserve">'''Astronomia''', que [[etimologia|etimologicamente]] significa "''[[lei]] das [[estrela]]s''",(do [[Grego]]): &#940;&#963;&#964;&#961;&#959;, + [[nomos|&#957;&#972;&#956;&#959;&#962;]]) é uma [[ciência]] que envolve a [[observação]] and explicação de [[evento]]s que ocorrem fora da [[Terra]] e de sua [[atmosfera]]. Estuda as origens, evolução e propriedades físicas e químicas de todos os objectos que podem ser observados no céu (e estão além da Terra), bem como todos os processos que os involvem.
Que subcampos ela inclui é uma questão cuja resposta tem mudado com o tempo. Durante parte do [[Século 20]] a astronomia era dividida em [[astrometria]], [[mecânica celeste]] and [[astrofísica]]. Dos três, a astrofísica ganhou uma certa preeminência, como pode ser visto nos nomes dos departamentos e institutos universitários envolvidos em pesquisa astronômica: Os mais antigos são invariavelmente departamentos e institutos de ''Astronomia'', enquanto os mais novos tendem a incluir astrofísica em seus nomes, algumas vezes excluindo a palavra astronomia, para enfatizar a natureza de seua pesquisa. Além disso, pesquisa astrofísica, especialmente em [[astrofísica teórica]] pode ser realizada por pessoas cujo background é em [[física]] ou [[matemática]], ao invés de astronomia.
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[imagem:moon.crater.arp.300pix.jpg]]<br><small>
'' '''Astronomia lunar:''' o lado escuro da Lua. A grande bacia mostrada é a Cratera 308. Ela cobre cerca de 30 quilômetros e foi fotografada pela tripulação da [[Apollo 11]] enquanto eles estavam circundando a lua em [[1969]]''<br>
[[media:moon.crater.arp.750pix.jpg|Versão grande<br>]]<br>
</small>
</div>
A Astronomia é uma das poucas ciências onde [[astronomia amadora|amadores]] possuem um papel ativo, especialmente na descoberta e monitoração de [[fenômeno]]s temporários. Astronomia não deve ser confundida com [[astrologia]], uma [[pseudo-ciência]] que tenta prever o destino de uma pessoa acompanhando os caminhos de objetos astronômicos. Embora os dois campos compartilhem uma origem comum eles são bastante diferentes; a astronomia incorpora o [[método científico]], enquanto a astrologia, sem bases científicas, não o faz.
==Divisões da Astronomia==
Devido ao seu escopo gigantesco, a astronomia é dividida em várias áreas. Uma distinção principal é entre a astronomia ''teórica'' e a ''observacional''. ''Observadores'' usam vários meios para obter dados sobre diversos fenômenos, que são usados pelos ''teóricos'' para criar e testar teorias e modelos, para explicar observações e para prever novos resultados; observador e teórico não são necessariamente pessoas diferentes e, ao invés de dois campos perfeitamente delimitados, há um contínuo de cientistas que pôem maios ou menor ênfase em observação ou teoria.
Fields of study are also categorized in another two ways: by ''subject'', usually according to the region of space (e.g. Galactic astronomy) or ''problems addressed'' (such as star formation or cosmology); or by the way used for obtaining information
(essentially, what region of the [[electromagnetic spectrum]] is used). While the first division is applicable to both observers and theorist, the second one applies only to observers
(imperfectly), as theorists try to use all the information available, in all wavelength, and observers often
observe in more than one region of the spectrum.
===By subject or problem addressed===
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:dust.devil.mars.arp.300pix.jpg]]<br><small>
'' '''Planetary astronomy, or Planetary Sciences:''' a Martian dust devil. Photographed by the NASA Global Surveyor in Mars orbit, the long dark streak is formed by the movement of a swirling column of Martian atmosphere (with similarities to a terrestrial tornado). The dust devil (the black spot) is climbing the crater wall. Dust devils occur when the atmosphere is heated by a warm surface and begins to spin as it rises. The streaks in the right hand half of the picture are sand dunes on the crater floor.''<br>
[[media:dust.devil.mars.arp.750pix.jpg|Larger version<br>]]<br>
</small>
</div>
*[[Astrometry]]: Measures positions of objects in the sky and their changes.Necessary to define the system of coordinates used and the [[kinematics]] of object in our galaxy.
*[[Cosmology|Observational cosmology]]: Study of the universe as a whole and its evolution.
*[[Galactic astronomy]]: It used to be the study of the structure and components of our galaxy. Now includes study of other galaxies that can be observed in detail.
*[[Extragalactic astronomy]]: Study of objects (mainly galaxies) outside our galaxy.
*[[Galaxy formation and evolution]]: Study of the formation of the galaxies, and its evolution to the observed present state.
*[[Star formation]]: Study of the condition and processes that led to the formation of stars in the interior of gas clouds, and the process of formation itself.
*[[Stellar evolution]]: Study of the evolution of stars from its formation to its end as a stellar remnant.
*[[Stellar astronomy]]: Study of stars, in general.
See [[list of astronomical topics]] for a more exhaustive list of astronomy-related pages.
===By ways of obtaining information===
In astronomy, the main way of obtaining information is through
the detection and analysis of [[electromagnetic radiation]],
[[photon|photons]], but information is also carried by [[cosmic ray]]s, [[neutrino|neutrinos]], and, in the near future, [[gravitational wave|gravitational waves]] (see [[LIGO]] and [[LISA]]).
A traditional division of astronomy is given by the region of
the [[electromagnetic spectrum]] observed:
*[[Optical astronomy]] refers to the techniques used to detect and analyze [[light]] in and slightly around the [[wavelength]]s than can be detected with the [[eye]]s (about 400 - 800 nm). The most common tool is the [[telescope]], with [[electronic imager]]s and [[spectrograph]]s.
*[[Infrared astronomy]] deals with the detection of infrared radiation (wavelengths longer than red light). The most common tool is the [[telescope]] but with the instrument optimized for infrared. [[Space telescope]]s are also used to eliminate noise (electromagnetic interference) from the atmosphere.
*[[Radio astronomy]] uses completely different instruments to detect [[radiation]] of wavelengths of mm to cm. The receivers are similar to those used in [[radio]] broadcast transmission (which uses those wavelengths of radiation). See also [[Radio telescope]]s.
*[[High-energy astronomy]]
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:grav.lens1.arp.300pix.jpg]]<br><small>
'' '''Extragalactic astronomy''': gravitational lensing. This Hubble Space Telescope image shows several blue, loop-shaped objects that actually are multiple images of the same galaxy. They have been duplicated by the gravitational lens effect of the cluster of yellow, elliptical and spiral galaxies near the photograph's center. The gravitational lens is produced by the cluster's tremendous gravitational field that bends light to magnify, brighten and distort the image of a more distant object.'' <br>'''Click on the picture for more information and a larger version.'''
</small>
</div>
Optical and radio astronomy can be performed with ground-based [[observatory|observatories]], because the [[Earth's atmosphere|atmosphere]] is transparent at those wavelengths. Infrared light is heavily absorbed by
[[water vapor]], so infrared observatories have to be located in high, dry places or in space.
The atmosphere is opaque at the wavelengths used by [[X-ray astronomy]], [[gamma-ray astronomy]], [[UV astronomy]] and, except for a few wavelength "windows", [[Far infrared astronomy]] , and so observations
can be carried out only from [[balloon]]s or [[space observatory|space observatories]].
==Short history==
In the early part of its history, astronomy involved only the observation and predictions of the motions of the objects in the sky that could be seen with the naked eye. The [[Rigveda]] refers to the 27 [[constellations]] associated with the motions of the sun and also the 12 [[Zodiac|zodiacal]] divisions of the sky. The [[Hellenic civilization|ancient Greeks]] made important contributions to astronomy, among them the definition of the [[apparent magnitude|magnitude]] system. The [[Bible]] contains a number of statements on the position of the earth in the universe and the nature of the stars and planets, most of which are poetic rather than literal; see [[Biblical cosmology]]. In [[500|500 AD]], [[Aryabhata]] presented a mathematical system that took the earth to spin on its axis and considered the motions of the planets with respect to the sun.
The study of astronomy almost stopped during the middle ages, except for
the work of [[Arab|Arabic]] astronomers. In the late 9th century the Islamic astronomer al-Farghani (Abu'l-Abbas Ahmad ibn Muhammad ibn Kathir al-Farghani) wrote extensively on the motion of celestial bodies. In the 12th century, his works were translated into Latin, and it is said that Dante got his astronomical knowledge from al-Farghani's books.
In the late [[10th century]], a huge [[observatory]] was built near [[Tehran]], [[Iran]], by the astronomer al-Khujandi who observed a series of meridian transits of the Sun, which allowed him to calculate the obliquity of the ecliptic, also known as the tilt of the Earth's axis relative to the Sun. As we know today, the Earth's tilt is approximately 23&deg;34', and al-Khujandi measured it as being 23&deg;32'19". Using this information, he also compiled a list of [[latitude]]s and [[longitude]]s of major cities.
[[Omar Khayyam]] (Ghiyath al-Din Abu'l-Fath Umar ibn Ibrahim al-Nisaburi al-Khayyami) was a great [[Persia]]n scientist, philosopher, and poet who lived from [[1048]]-[[1131]]. He compiled many astronomical tables and performed a reformation of the [[calendar]] which was more accurate than the [[Julian Calendar|Julian]] and came close to the [[Gregorian calendar|Gregorian]]. An amazing feat was his calculation of the year to be 365.24219858156 days long, which is accurate to the 6th decimal place.
During the [[renaissance]] [[Copernicus]] proposed a [[heliocentric model]] of the [[Solar System]]. His work was defended, expanded upon, and corrected by [[Galileo Galilei]] and [[Johannes Kepler]]. Kepler was the first to devise a system which described correctly the details of the motion of the planets with the Sun at the center. However, Kepler did not understand the reasons behind the laws he wrote down. It was left to [[Sir Isaac Newton|Newton's]] invention of [[celestial dynamics]] and his [[law of gravitation]] to finally explain the motions of the [[planet]]s.
Stars were found to be far away objects. With the advent of [[spectroscopy]] it was proved that they were similar to our own sun, but with a wide range of [[temperature]]s, [[mass]]es and sizes. The existence of our [[galaxy]], the [[Milky Way]], as a separate group of stars was only proven in the 20th century, along with the existence of "external" galaxies, and soon after, the expansion of the [[universe]] seen in the recession of most galaxies from us. [[Cosmology]] made huge advances during the 20th century, with the model of the [[big bang]] heavily supported by the evidence provided by astronomy and physics, such as the [[cosmic microwave background radiation]], [[Hubble's Law]] and [[big bang nucleosynthesis|cosmological abundances of elements]].
For a more detailed history of astronomy, see the [[history of astronomy]].
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[image:ant.nebula.arp.300pix.jpg]]<br><small>
'' '''Stellar astronomy,Stellar evolution:''' The Ant planetary nebula. The ejection of gas, from the dying star at the center, has intriguing symmetrical patterns unlike the chaotic patterns expected from an ordinary explosion. Scientists using Hubble would like to understand how a spherical star can produce such prominent symmetries in the gas that it ejects.''<br>
'''Click on the picture for more information and a larger version.'''
</small>
</div>
== See also ==
* [[Astronomer|Astronomers and Astrophysicists]]
* [[space science]]...
* [[Timeline of black hole physics]]
* [[Timeline of cosmology]]
* [[Timeline of cosmic microwave background astronomy]]
* [[Timeline of other background radiation fields]]
* [[Timeline of galaxies, clusters of galaxies, and large scale structure]]
* [[Timeline of the interstellar medium and intergalactic medium]]
* [[Timeline of white dwarfs, neutron stars, and supernovae]]
* [[Timeline of stellar astronomy]]
* [[Timeline of solar astronomy]]
* [[Timeline of solar system astronomy]]
* [[Timeline of astronomical maps, catalogs, and surveys]]
* [[Timeline of telescopes, observatories, and observing technology]]
* [[Timeline of artificial satellites and space probes]]
* [[International Astronomical Union]]
* [[American Astronomical Society]]
* [[Royal Astronomical Society]]
* [[European Southern Observatory]]
==Astronomy Tools==
http://www.asimpleclick.com/nasa_related.htm for additional info
* [[Telescope]]
* [[Computers]]
* [[Calculator]]
* [[Observatory]]
* [[Space observatory]]
==External links==
===Organizations===
*[http://www.aavso.org/ American Association of Variable Star Observers]
*[http://www.drastronomy.com/ Durham Region Astronomical Association]
*[http://www.noao.edu/ National Optical Astronomy Observatories]
*[http://www.nyaa-starfest.com/ North York Astronomical Association]
*[http://www.rasc.ca/ Royal Astronomical Society of Canada]
*[http://www.ras.org.uk/ Royal Astronomical Society (UK)]
*[http://www.astro.cz/ Czech Astronomical Society]
*[http://www.hia-iha.nrc-cnrc.gc.ca/ Herzberg Institute of Astrophysics]
*[http://www.slasonline.org/ Saint Louis Astronomical Society]
===References===
*[http://www.ency-astro.com/ Encyclopedia of Astronomy and Astrophysics]
*[http://xxx.lanl.gov/ Los Alamos Astrophysics e-Print Database]
*[http://antwrp.gsfc.nasa.gov/apod/ Astronomy Picture of the Day]
*[http://www.phys-astro.sonoma.edu/BruceMedalists/ 20th Century Astronomers]
*[http://physics.unr.edu/grad/welser/astro/arab.html Islamic and Arab Astronomy]
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<text xml:space="preserve">'''Astronomia''', que [[etimologia|etimologicamente]] significa "''[[lei]] das [[estrela]]s''",(do [[Grego]]): &#940;&#963;&#964;&#961;&#959;, + [[nomos|&#957;&#972;&#956;&#959;&#962;]]) é uma [[ciência]] que envolve a [[observação]] and explicação de [[evento]]s que ocorrem fora da [[Terra]] e de sua [[atmosfera]]. Estuda as origens, evolução e propriedades físicas e químicas de todos os objectos que podem ser observados no céu (e estão além da Terra), bem como todos os processos que os involvem.
Que subcampos ela inclui é uma questão cuja resposta tem mudado com o tempo. Durante parte do [[Século 20]] a astronomia era dividida em [[astrometria]], [[mecânica celeste]] and [[astrofísica]]. Dos três, a astrofísica ganhou uma certa preeminência, como pode ser visto nos nomes dos departamentos e institutos universitários envolvidos em pesquisa astronômica: Os mais antigos são invariavelmente departamentos e institutos de ''Astronomia'', enquanto os mais novos tendem a incluir astrofísica em seus nomes, algumas vezes excluindo a palavra astronomia, para enfatizar a natureza de seua pesquisa. Além disso, pesquisa astrofísica, especialmente em [[astrofísica teórica]] pode ser realizada por pessoas cujo background é em [[física]] ou [[matemática]], ao invés de astronomia.
<div style="float:right; clear:right; margin-left:10px; margin-right:10px; width:300px; text-align:center">
[[imagem:moon.crater.arp.300pix.jpg]]<br><small>
'' '''Astronomia lunar:''' o lado escuro da Lua. A grande bacia mostrada é a Cratera 308. Ela cobre cerca de 30 quilômetros e foi fotografada pela tripulação da [[Apollo 11]] enquanto eles estavam circundando a lua em [[1969]]''<br>
[[media:moon.crater.arp.750pix.jpg|Versão grande<br>]]<br>
</small>
</div>
A Astronomia é uma das poucas ciências onde [[astronomia amadora|amadores]] possuem um papel ativo, especialmente na descoberta e monitoração de [[fenômeno]]s temporários. Astronomia não deve ser confundida com [[Astrologia]], uma [[pseudo-ciência]] que tenta prever o destino de uma pessoa acompanhando os caminhos de objetos astronômicos. Embora os dois campos compartilhem uma origem comum eles são bastante diferentes; a astronomia incorpora o [[método científico]], enquanto a astrologia, sem bases científicas, não o faz.
==Divisões da Astronomia==
Devido ao seu escopo gigantesco, a astronomia é dividida em várias áreas. Uma distinção principal é entre a astronomia ''teórica'' e a ''observacional''. ''Observadores'' usam vários meios para obter dados sobre diversos fenômenos, que são usados pelos ''teóricos'' para criar e testar teorias e modelos, para explicar observações e para prever novos resultados; observador e teórico não são necessariamente pessoas diferentes e, ao invés de dois campos perfeitamente delimitados, há um contínuo de cientistas que pôem maios ou menor ênfase em observação ou teoria.
Campos de estudo são também categorizados por outras duas formas: Por ''assunto'', em geral de acordo com a região do espaço (Ex. [[Astronomia Galáctica]]) ou ''problemas atacados'' (tais como formação das estrelas ou [[cosmologia]]); ou pelo método usado para obter informação (essencialmente, que faixa do [[espectro eletromagnético]] é usada). Enquanto a primeira divisão se aplica tanto a observadores como também a teóricos, a segunda se aplica aplica a observadores, pois os teóricos tentam usar toda a informação disponível, em todas os comprimentos de onda, e observadores freqüentemente observam em mais de uma faixa do espectro.
===Por assunto ou problema atacado===
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'' '''[[Astronomia Planetária]] ou Ciências Planetárias:''' a Martian dust devil. Photographed by the NASA Global Surveyor in Mars orbit, the long dark streak is formed by the movement of a swirling column of Martian atmosphere (with similarities to a terrestrial tornado). The dust devil (the black spot) is climbing the crater wall. Dust devils occur when the atmosphere is heated by a warm surface and begins to spin as it rises. The streaks in the right hand half of the picture are sand dunes on the crater floor.''<br>
[[media:dust.devil.mars.arp.750pix.jpg|Larger version<br>]]<br>
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*[[Astrometria]]: Mede as posições dos objetos no céu e suas mudanças. É necessária para definir o sistema de coordenadas usado e a [[cinemática]] de objetos em nossa [[galáxia]].
*[[Cosmologia|Cosmologia Observacional]]: Estudo do universo como um todo e sua evolução.
*[[Astronomia Galáctica]]: Costumava ser o estudo da estrutura e componentes de nossa galáxia. Agora inclui o estudo de outras galáxias que possam ser observadas em detalhe
*[[Astronomia Extragaláctica]]: Estudo de objetos (principalmente galáxias) fora de nossa galáxia.
*[[Formação e evolução de galáxias]]: Study of the formation of the galaxies, and its evolution to the observed present state.
*[[Star formation]]: Study of the condition and processes that led to the formation of stars in the interior of gas clouds, and the process of formation itself.
*[[Stellar evolution]]: Study of the evolution of stars from its formation to its end as a stellar remnant.
*[[Stellar astronomy]]: Study of stars, in general.
See [[list of astronomical topics]] for a more exhaustive list of astronomy-related pages.
===By ways of obtaining information===
In astronomy, the main way of obtaining information is through
the detection and analysis of [[electromagnetic radiation]],
[[photon|photons]], but information is also carried by [[cosmic ray]]s, [[neutrino|neutrinos]], and, in the near future, [[gravitational wave|gravitational waves]] (see [[LIGO]] and [[LISA]]).
A traditional division of astronomy is given by the region of
the [[electromagnetic spectrum]] observed:
*[[Optical astronomy]] refers to the techniques used to detect and analyze [[light]] in and slightly around the [[wavelength]]s than can be detected with the [[eye]]s (about 400 - 800 nm). The most common tool is the [[telescope]], with [[electronic imager]]s and [[spectrograph]]s.
*[[Infrared astronomy]] deals with the detection of infrared radiation (wavelengths longer than red light). The most common tool is the [[telescope]] but with the instrument optimized for infrared. [[Space telescope]]s are also used to eliminate noise (electromagnetic interference) from the atmosphere.
*[[Radio astronomy]] uses completely different instruments to detect [[radiation]] of wavelengths of mm to cm. The receivers are similar to those used in [[radio]] broadcast transmission (which uses those wavelengths of radiation). See also [[Radio telescope]]s.
*[[High-energy astronomy]]
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'' '''Extragalactic astronomy''': gravitational lensing. This Hubble Space Telescope image shows several blue, loop-shaped objects that actually are multiple images of the same galaxy. They have been duplicated by the gravitational lens effect of the cluster of yellow, elliptical and spiral galaxies near the photograph's center. The gravitational lens is produced by the cluster's tremendous gravitational field that bends light to magnify, brighten and distort the image of a more distant object.'' <br>'''Click on the picture for more information and a larger version.'''
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Optical and radio astronomy can be performed with ground-based [[observatory|observatories]], because the [[Earth's atmosphere|atmosphere]] is transparent at those wavelengths. Infrared light is heavily absorbed by
[[water vapor]], so infrared observatories have to be located in high, dry places or in space.
The atmosphere is opaque at the wavelengths used by [[X-ray astronomy]], [[gamma-ray astronomy]], [[UV astronomy]] and, except for a few wavelength "windows", [[Far infrared astronomy]] , and so observations
can be carried out only from [[balloon]]s or [[space observatory|space observatories]].
==Short history==
In the early part of its history, astronomy involved only the observation and predictions of the motions of the objects in the sky that could be seen with the naked eye. The [[Rigveda]] refers to the 27 [[constellations]] associated with the motions of the sun and also the 12 [[Zodiac|zodiacal]] divisions of the sky. The [[Hellenic civilization|ancient Greeks]] made important contributions to astronomy, among them the definition of the [[apparent magnitude|magnitude]] system. The [[Bible]] contains a number of statements on the position of the earth in the universe and the nature of the stars and planets, most of which are poetic rather than literal; see [[Biblical cosmology]]. In [[500|500 AD]], [[Aryabhata]] presented a mathematical system that took the earth to spin on its axis and considered the motions of the planets with respect to the sun.
The study of astronomy almost stopped during the middle ages, except for
the work of [[Arab|Arabic]] astronomers. In the late 9th century the Islamic astronomer al-Farghani (Abu'l-Abbas Ahmad ibn Muhammad ibn Kathir al-Farghani) wrote extensively on the motion of celestial bodies. In the 12th century, his works were translated into Latin, and it is said that Dante got his astronomical knowledge from al-Farghani's books.
In the late [[10th century]], a huge [[observatory]] was built near [[Tehran]], [[Iran]], by the astronomer al-Khujandi who observed a series of meridian transits of the Sun, which allowed him to calculate the obliquity of the ecliptic, also known as the tilt of the Earth's axis relative to the Sun. As we know today, the Earth's tilt is approximately 23&deg;34', and al-Khujandi measured it as being 23&deg;32'19". Using this information, he also compiled a list of [[latitude]]s and [[longitude]]s of major cities.
[[Omar Khayyam]] (Ghiyath al-Din Abu'l-Fath Umar ibn Ibrahim al-Nisaburi al-Khayyami) was a great [[Persia]]n scientist, philosopher, and poet who lived from [[1048]]-[[1131]]. He compiled many astronomical tables and performed a reformation of the [[calendar]] which was more accurate than the [[Julian Calendar|Julian]] and came close to the [[Gregorian calendar|Gregorian]]. An amazing feat was his calculation of the year to be 365.24219858156 days long, which is accurate to the 6th decimal place.
During the [[renaissance]] [[Copernicus]] proposed a [[heliocentric model]] of the [[Solar System]]. His work was defended, expanded upon, and corrected by [[Galileo Galilei]] and [[Johannes Kepler]]. Kepler was the first to devise a system which described correctly the details of the motion of the planets with the Sun at the center. However, Kepler did not understand the reasons behind the laws he wrote down. It was left to [[Sir Isaac Newton|Newton's]] invention of [[celestial dynamics]] and his [[law of gravitation]] to finally explain the motions of the [[planet]]s.
Stars were found to be far away objects. With the advent of [[spectroscopy]] it was proved that they were similar to our own sun, but with a wide range of [[temperature]]s, [[mass]]es and sizes. The existence of our [[galaxy]], the [[Milky Way]], as a separate group of stars was only proven in the 20th century, along with the existence of "external" galaxies, and soon after, the expansion of the [[universe]] seen in the recession of most galaxies from us. [[Cosmology]] made huge advances during the 20th century, with the model of the [[big bang]] heavily supported by the evidence provided by astronomy and physics, such as the [[cosmic microwave background radiation]], [[Hubble's Law]] and [[big bang nucleosynthesis|cosmological abundances of elements]].
For a more detailed history of astronomy, see the [[history of astronomy]].
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'' '''Stellar astronomy,Stellar evolution:''' The Ant planetary nebula. The ejection of gas, from the dying star at the center, has intriguing symmetrical patterns unlike the chaotic patterns expected from an ordinary explosion. Scientists using Hubble would like to understand how a spherical star can produce such prominent symmetries in the gas that it ejects.''<br>
'''Click on the picture for more information and a larger version.'''
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== See also ==
* [[Astronomer|Astronomers and Astrophysicists]]
* [[space science]]...
* [[Timeline of black hole physics]]
* [[Timeline of cosmology]]
* [[Timeline of cosmic microwave background astronomy]]
* [[Timeline of other background radiation fields]]
* [[Timeline of galaxies, clusters of galaxies, and large scale structure]]
* [[Timeline of the interstellar medium and intergalactic medium]]
* [[Timeline of white dwarfs, neutron stars, and supernovae]]
* [[Timeline of stellar astronomy]]
* [[Timeline of solar astronomy]]
* [[Timeline of solar system astronomy]]
* [[Timeline of astronomical maps, catalogs, and surveys]]
* [[Timeline of telescopes, observatories, and observing technology]]
* [[Timeline of artificial satellites and space probes]]
* [[International Astronomical Union]]
* [[American Astronomical Society]]
* [[Royal Astronomical Society]]
* [[European Southern Observatory]]
==Astronomy Tools==
http://www.asimpleclick.com/nasa_related.htm for additional info
* [[Telescope]]
* [[Computers]]
* [[Calculator]]
* [[Observatory]]
* [[Space observatory]]
==External links==
===Organizations===
*[http://www.aavso.org/ American Association of Variable Star Observers]
*[http://www.drastronomy.com/ Durham Region Astronomical Association]
*[http://www.noao.edu/ National Optical Astronomy Observatories]
*[http://www.nyaa-starfest.com/ North York Astronomical Association]
*[http://www.rasc.ca/ Royal Astronomical Society of Canada]
*[http://www.ras.org.uk/ Royal Astronomical Society (UK)]
*[http://www.astro.cz/ Czech Astronomical Society]
*[http://www.hia-iha.nrc-cnrc.gc.ca/ Herzberg Institute of Astrophysics]
*[http://www.slasonline.org/ Saint Louis Astronomical Society]
===References===
*[http://www.ency-astro.com/ Encyclopedia of Astronomy and Astrophysics]
*[http://xxx.lanl.gov/ Los Alamos Astrophysics e-Print Database]
*[http://antwrp.gsfc.nasa.gov/apod/ Astronomy Picture of the Day]
*[http://www.phys-astro.sonoma.edu/BruceMedalists/ 20th Century Astronomers]
*[http://physics.unr.edu/grad/welser/astro/arab.html Islamic and Arab Astronomy]
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<text xml:space="preserve">'''Astronomia''', que [[etimologia|etimologicamente]] significa "''[[lei]] das [[estrela]]s''",(do [[Grego]]): &#940;&#963;&#964;&#961;&#959;, + [[nomos|&#957;&#972;&#956;&#959;&#962;]]) é uma [[ciência]] que envolve a [[observação]] and explicação de [[evento]]s que ocorrem fora da [[Terra]] e de sua [[atmosfera]]. Estuda as origens, evolução e propriedades físicas e químicas de todos os objectos que podem ser observados no céu (e estão além da Terra), bem como todos os processos que os involvem.
Que subcampos ela inclui é uma questão cuja resposta tem mudado com o tempo. Durante parte do [[Século 20]] a astronomia era dividida em [[astrometria]], [[mecânica celeste]] and [[astrofísica]]. Dos três, a astrofísica ganhou uma certa preeminência, como pode ser visto nos nomes dos departamentos e institutos universitários envolvidos em pesquisa astronômica: Os mais antigos são invariavelmente departamentos e institutos de ''Astronomia'', enquanto os mais novos tendem a incluir astrofísica em seus nomes, algumas vezes excluindo a palavra astronomia, para enfatizar a natureza de seua pesquisa. Além disso, pesquisa astrofísica, especialmente em [[astrofísica teórica]] pode ser realizada por pessoas cujo background é em [[física]] ou [[matemática]], ao invés de astronomia.
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'' '''Astronomia lunar:''' o lado escuro da Lua. A grande bacia mostrada é a Cratera 308. Ela cobre cerca de 30 quilômetros e foi fotografada pela tripulação da [[Apollo 11]] enquanto eles estavam circundando a lua em [[1969]]''<br>
[[media:moon.crater.arp.750pix.jpg|Versão grande<br>]]<br>
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A Astronomia é uma das poucas ciências onde [[astronomia amadora|amadores]] possuem um papel ativo, especialmente na descoberta e monitoração de [[fenômeno]]s temporários. Astronomia não deve ser confundida com [[Astrologia]], uma [[pseudo-ciência]] que tenta prever o destino de uma pessoa acompanhando os caminhos de objetos astronômicos. Embora os dois campos compartilhem uma origem comum