Aurora
An aurora (plural: auroras or aurorae ), [a] sometimes referred to as polar lights , northern lights (aurora borealis) or southern lights (aurora australis), is a natural light display in the Earth's sky, predominantly seen in the high-latitude regions (around the Arctic and Antarctic ).
Page Revisions
| Year | Metadata | Sections | Top Words | First Paragraph |
| 2018 |
223960 characters 21 sections 58 paragraphs 28 images 267 internal links 133 external links |
2. Occurrence of terrestrial auroras 4. Interaction of the solar wind with Earth 5. Auroral particle acceleration 6. Auroral events of historical significance |
auroral 0.460 auroras 0.449 aurora 0.399 geomagnetic 0.180 magnetic 0.166 field 0.145 electrons 0.139 currents 0.091 magnetosphere 0.089 lines 0.085 lights 0.084 arcs 0.082 diffuse 0.079 electric 0.075 acceleration 0.075 |
An aurora (plural: auroras or aurorae ), [a] sometimes referred to as polar lights , northern lights (aurora borealis) or southern lights (aurora australis), is a natural light display in the Earth's sky, predominantly seen in the high-latitude regions (around the Arctic and Antarctic ). |
| 2017 |
228137 characters 21 sections 64 paragraphs 36 images 263 internal links 129 external links |
2. Occurrence of terrestrial auroras 4. Interaction of the solar wind with Earth 5. Auroral particle acceleration 6. Auroral events of historical significance |
auroral 0.466 auroras 0.436 aurora 0.390 geomagnetic 0.182 magnetic 0.172 field 0.146 electrons 0.141 estonia 0.099 currents 0.092 magnetosphere 0.090 lines 0.086 lights 0.085 arcs 0.082 diffuse 0.080 electric 0.076 |
An aurora (plural: auroras ), [a] sometimes referred to as polar lights , northern lights ( aurora borealis ) or southern lights ( aurora australis ), is a natural light display in the Earth's sky, predominantly seen in the high latitude regions (around the Arctic and Antarctic ). |
| 2016 |
218581 characters 20 sections 62 paragraphs 32 images 253 internal links 121 external links |
1. Occurrence of terrestrial auroras 3. Interaction of the solar wind with Earth 4. Auroral particle acceleration 5. Auroral events of historical significance |
auroral 0.484 auroras 0.435 aurora 0.382 geomagnetic 0.181 magnetic 0.176 field 0.143 electrons 0.140 currents 0.099 estonia 0.099 lights 0.095 magnetosphere 0.090 lines 0.086 arcs 0.082 electric 0.082 diffuse 0.080 |
An aurora , sometimes referred to as a polar light or northern light , is a natural light display in the sky, predominantly seen in the high latitude ( Arctic and Antarctic ) regions. [a] Auroras are produced when the magnetosphere is sufficiently disturbed by the solar wind that the trajectories of charged particles in both solar wind and magnetospheric plasma , mainly in the form of electrons and protons, precipitate them into the upper atmosphere ( thermosphere / exosphere ), where their energy is lost. The resulting ionization and excitation of atmospheric constituents emits light of varying colour and complexity. The form of the aurora, occurring within bands around both polar regions, is also dependent on the amount of acceleration imparted to the precipitating particles. Precipitating protons generally produce optical emissions as incident hydrogen atoms after gaining electrons from the atmosphere. Proton auroras are usually observed at lower latitudes. [2] Different aspects of an aurora are elaborated in various sections below. |
| 2015 |
216542 characters 19 sections 52 paragraphs 29 images 254 internal links 116 external links |
1. Occurrence of terrestrial auroras 3. Interaction of the solar wind with Earth 4. Auroral particle acceleration 5. Auroral events of historical significance |
auroral 0.482 auroras 0.452 aurora 0.360 magnetic 0.184 geomagnetic 0.181 field 0.154 electrons 0.140 currents 0.099 lights 0.094 plasma 0.093 electric 0.092 lines 0.086 magnetosphere 0.084 acceleration 0.082 electron 0.080 |
An aurora , sometimes referred to as a polar light , is a natural light display in the sky, predominantly seen in the high latitude ( Arctic and Antarctic ) regions. [nb 1] Auroras are produced when the magnetosphere is sufficiently disturbed by the solar wind that the trajectories of charged particles in both solar wind and magnetospheric plasma , mainly in the form of electrons and protons, precipitate them into the upper atmosphere ( thermosphere / exosphere ), where their energy is lost. The resulting ionization and excitation of atmospheric constituents emits light of varying colour and complexity. The form of the aurora, occurring within bands around both polar regions, is also dependent on the amount of acceleration imparted to the precipitating particles. Precipitating protons generally produce optical emissions as incident hydrogen atoms after gaining electrons from the atmosphere. Proton auroras are usually observed at lower latitudes. [2] Different aspects of an aurora are elaborated in various sections below. |
| 2014 |
191720 characters 17 sections 44 paragraphs 26 images 231 internal links 88 external links |
1. Occurrence of terrestrial auroras 3. Interaction of the solar wind with Earth 4. Auroral particle acceleration 5. Auroral events of historical significance |
auroral 0.498 auroras 0.447 aurora 0.357 geomagnetic 0.190 magnetic 0.189 field 0.156 electrons 0.126 currents 0.104 lines 0.090 electric 0.086 magnetosphere 0.082 arcs 0.078 diffuse 0.076 1859 0.075 plasma 0.074 |
An aurora is a natural light display in the sky (from the Latin word aurora , "sunrise" or the Roman goddess of dawn ), predominantly seen in the high latitude ( Arctic and Antarctic ) regions. The name ”auroras” is now more commonly used for the linguistic plural ”aurorae” of ”aurora”, so is adopted throughout the main text of this article. Modern style guides recommend that the names of meteorological phenomena, such as aurora borealis , be uncapitalized. [1] Auroras are caused by charged particles, mainly electrons and protons, entering the atmosphere from above causing ionisation and excitation of atmospheric constituents, and consequent optical emissions. Incident protons can also produce emissions as hydrogen atoms after gaining an electron from the atmosphere. |
| 2013 |
189758 characters 15 sections 61 paragraphs 31 images 250 internal links 100 external links |
4. Solar wind and the magnetosphere 6. Auroral events of historical significance 9. Sounds associated with auroras |
aurora 0.436 auroral 0.419 auroras 0.316 magnetic 0.263 field 0.176 aurorae 0.145 lines 0.142 electrons 0.137 currents 0.122 geomagnetic 0.103 wind 0.101 imf 0.088 1859 0.081 plasma 0.080 glow 0.079 |
An aurora (plural: aurorae or auroras; from the Latin word aurora , "sunrise" or the Roman goddess of dawn) is a natural light display in the sky particularly in the high latitude ( Arctic and Antarctic ) regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere ( thermosphere ). The charged particles originate in the magnetosphere and solar wind and, on Earth, are directed by the Earth's magnetic field into the atmosphere. Most aurorae occur in a band known as the auroral zone , [1] [2] which is typically in 3° to 6° latitudinal extent of geographical poles , or equivalently, 10° to 20° latitudinal extent of geomagnetic poles , and at all local times or longitudes. During a geomagnetic storm , the auroral zone expands to lower latitudes. |
| 2012 |
175932 characters 15 sections 59 paragraphs 29 images 237 internal links 89 external links |
3. Solar wind and the magnetosphere 5. Auroral events of historical significance 8. Sounds associated with auroras 10. History of aurora theories |
aurora 0.435 auroral 0.423 auroras 0.317 magnetic 0.277 field 0.180 lines 0.147 electrons 0.142 currents 0.127 wind 0.101 geomagnetic 0.096 imf 0.091 boston 0.089 1859 0.084 plasma 0.083 glow 0.082 |
An aurora (plural: aurorae or auroras; from the Latin word aurora , "dawn") is a natural light display in the sky particularly in the high latitude ( Arctic and Antarctic ) regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere ( thermosphere ). The charged particles originate in the magnetosphere and solar wind and, on Earth, are directed by the Earth's magnetic field into the atmosphere. Aurora is classified as diffuse or discrete aurora. Most aurorae occur in a band known as the auroral zone , [1] [2] which is typically 3° to 6° in latitudinal extent and at all local times or longitudes. The auroral zone is typically 10° to 20° from the magnetic pole defined by the axis of the Earth's magnetic dipole. During a geomagnetic storm , the auroral zone will expand to lower latitudes. |
| 2011 |
173568 characters 14 sections 63 paragraphs 37 images 231 internal links 70 external links |
3. Solar wind and the magnetosphere 5. Auroral events of historical significance |
aurora 0.438 auroral 0.426 auroras 0.319 magnetic 0.269 field 0.181 lines 0.148 electrons 0.143 currents 0.127 wind 0.101 geomagnetic 0.097 imf 0.092 boston 0.090 1859 0.085 plasma 0.084 glow 0.083 |
An aurora (plural: auroras or aurorae ) is a natural light display in the sky particularly in the high latitude ( Arctic and Antarctic ) regions, caused by the collision of energetic charged particles with atoms in the high altitude atmosphere ( thermosphere ). The charged particles originate in the magnetosphere and solar wind and, on Earth, are directed by the Earth's magnetic field into the atmosphere. Aurora is classified as diffuse or discrete aurora. Most aurorae occur in a band known as the auroral zone [1] [2] which is typically 3° to 6° in latitudinal extent and at all local times or longitudes. The auroral zone is typically 10° to 20° from the magnetic pole defined by the axis of the Earth's magnetic dipole. During a geomagnetic storm , the auroral zone will expand to lower latitudes. The diffuse aurora is a featureless glow in the sky which may not be visible to the naked eye even on a dark night and defines the extent of the auroral zone. The discrete aurora are sharply defined features within the diffuse aurora which vary in brightness from just barely visible to the naked eye to bright enough to read a newspaper at night. Discrete aurorae are usually observed only in the night sky because they are not as bright as the sunlit sky. Aurorae occur occasionally poleward of the auroral zone as diffuse patches [3] or arcs (polar cap arcs [4] ) which are generally invisible to the naked eye. |
| 2010 |
125951 characters 15 sections 55 paragraphs 24 images 218 internal links 43 external links |
3. Solar wind and the magnetosphere 5. Auroral events of historical significance |
aurora 0.400 auroral 0.393 auroras 0.364 magnetic 0.280 field 0.187 lines 0.158 electrons 0.149 currents 0.140 wind 0.099 boston 0.099 1859 0.093 ions 0.088 imf 0.087 geomagnetic 0.083 portland 0.081 |
An aurora (plural: auroras or aurorae ) is a natural light display in the sky , particularly in the polar regions , caused by the collision of charged particles directed by the Earth's magnetic field . An aurora is usually observed at night and typically occurs in the ionosphere . It is also referred to as a polar aurora or, collectively, as polar lights . These phenomena are commonly visible between 60 and 72 degrees north and south latitudes, which place them in a ring just within the Arctic and Antarctic polar circles. [ citation needed ] Auroras do occur deeper inside the polar regions, but these are infrequent and often invisible to the naked eye. |
| 2009 |
110079 characters 15 sections 53 paragraphs 23 images 203 internal links 36 external links |
3. Solar wind and the magnetosphere |
aurora 0.430 auroral 0.404 auroras 0.299 magnetic 0.282 field 0.189 lines 0.162 electrons 0.153 currents 0.144 wind 0.102 boston 0.102 1859 0.096 ions 0.090 imf 0.089 geomagnetic 0.085 portland 0.083 |
Auroras , sometimes called the northern and southern (polar) lights or aurorae ( singular: aurora ), are natural light displays in the sky , usually observed at night , particularly in the polar regions . They typically occur in the ionosphere . They are also referred to as polar auroras . |
| 2008 |
106171 characters 16 sections 65 paragraphs 18 images 237 internal links 42 external links |
2. Auroral forms and magnetism 3. Solar wind and magnetosphere 5. Auroral events of historical significance |
aurora 0.403 auroral 0.396 magnetic 0.282 lights 0.274 field 0.181 electrons 0.167 lines 0.153 auroras 0.146 currents 0.131 aurorae 0.123 boston 0.100 1859 0.094 wind 0.092 northern 0.090 imf 0.087 |
Auroras , sometimes called the northern and southern (polar) lights or aurorae ( singular: aurora ), are natural light displays in the sky , usually observed at night , particularly in the polar regions . They typically occur in the ionosphere . They are also referred to as polar auroras . In northern latitudes , the effect is known as the aurora borealis , named after the Roman goddess of dawn, Aurora , and the Greek name for north wind, Boreas by Pierre Gassendi in 1621. [1] The aurora borealis is also called the northern polar lights , as it is only visible in the sky from the Northern Hemisphere , the chance of visibility increasing with proximity to the north magnetic pole , which is currently in the arctic islands of northern Canada . Aurorae seen near the magnetic pole may be high overhead, but from further away, they illuminate the northern horizon as a greenish glow or sometimes a faint red, as if the sun was rising from an unusual direction. The aurora borealis most often occurs from September to October and from March to April. The northern lights have had a number of names throughout history. The Cree people call this phenomenon the " Dance of the Spirits ." |
| 2007 |
82720 characters 14 sections 59 paragraphs 16 images 149 internal links 51 external links |
2. Auroral forms and magnetism 3. The solar wind and magnetosphere |
aurora 0.410 auroral 0.357 magnetic 0.284 lights 0.237 field 0.194 electrons 0.187 auroras 0.178 lines 0.171 currents 0.147 wind 0.098 magnetosphere 0.097 portland 0.091 aurorae 0.088 energy 0.084 boston 0.084 |
Auroras ( Polar Lights ; or aurorae , sing. : aurora ) are natural different colored light displays, which are usually observed in the night sky , particularly in the polar zone . Some scientists therefore call them "polar auroras" (or "aurorae polaris"). In northern latitudes, it is known as the aurora borealis , named after the Roman goddess of the dawn, Aurora , and the Greek name for north wind, Boreas . It often appears as a greenish glow (or sometimes a faint red), as if the sun were rising from an unusual direction. The aurora borealis is also called the northern [polar] lights , as it is only visible in the North sky from the Northern Hemisphere . The aurora borealis most often occurs from September to October and from March to April. |
| 2006 |
78390 characters 14 sections 56 paragraphs 11 images 169 internal links 57 external links |
2. Auroral forms and magnetism 3. The solar wind and magnetosphere |
aurora 0.454 auroral 0.397 magnetic 0.235 lights 0.187 field 0.177 electrons 0.172 auroras 0.169 lines 0.163 currents 0.151 glow 0.106 wind 0.096 portland 0.094 magnetosphere 0.091 boston 0.086 imf 0.084 |
The aurora is a bright glow observed in the night sky , usually in the polar zone . For this reason some scientists call it a "polar aurora" (or "aurora polaris"). In northern latitudes, it is known as the aurora borealis (IPA /ɔˈɹɔɹə bɔɹiˈælɪs/ ), which is named after the Roman goddess of the dawn, Aurora , and the Greek name for north wind, Boreas . Especially in Europe, it often appears as a reddish glow on the northern horizon, as if the sun were rising from an unusual direction. The aurora borealis is also called the northern lights since it is only visible in the North sky from the Northern Hemisphere . The aurora borealis most often occurs from September to October and from March to April. Its southern counterpart, aurora australis , has similar properties. |
| 2005 |
40418 characters 9 sections 46 paragraphs 7 images 52 internal links 30 external links |
1. Auroral forms and magnetism 2. The solar wind and magnetosphere |
aurora 0.454 auroral 0.439 magnetic 0.243 electrons 0.218 field 0.196 currents 0.180 lines 0.179 lights 0.137 auroras 0.101 electric 0.099 plasma 0.096 glow 0.090 arcs 0.090 norse 0.084 energy 0.084 |
The polar aurora is a glow observed in the night sky in the polar zone. It is also known as " northern lights " or " aurora borealis ," Latin for "northern dawn" since (in Europe especially) it often appears as a reddish glow on the northern horizon, as if the sun were rising from an unusual direction. Aurora borealis most often occurs from September to October and March to April. Its southern counterpart " aurora australis ," has identical properties, so scientists prefer "polar aurora" (or "aurora polaris"). |
| 2004 |
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auroral 0.546 aurora 0.413 magnetic 0.210 geomagnetic 0.199 sounds 0.181 aurorae 0.133 lights 0.118 field 0.110 substorms 0.109 energetic 0.105 particles 0.103 magnetosphere 0.094 energy 0.089 electrons 0.084 northern 0.081 |
Polar aurorae are optical phenomena characterized by colorful displays of light in the night sky . An auroral display in the Northern Hemisphere is called the aurora borealis , or the northern lights ; in the Southern Hemisphere it is called the aurora australis . Auroras are the most visible effect of the solar wind upon the Earth's atmosphere . The aurora occur when the Van Allen radiation belts become "overloaded" with energetic particles, which cascade down magnetic field lines and collide with the earth's upper atmosphere. The most powerful aurora tend to occur after coronal mass ejections . Aurora in Latin means dawn and Borealis comes from Boreas, the name of the Greek god of the northern wind. |
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| 2003 |
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2. The chemistry of the aurora |
auroral 0.530 aurora 0.434 geomagnetic 0.248 magnetic 0.229 substorms 0.136 field 0.126 magnetosphere 0.117 particles 0.114 energy 0.111 auroras 0.108 energetic 0.104 electrons 0.104 annulus 0.097 arcs 0.096 wind 0.086 |
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| 2002 |
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auroral 0.498 aurora 0.455 geomagnetic 0.297 magnetic 0.196 auroras 0.130 electrons 0.125 annulus 0.115 curtains 0.115 arcs 0.115 field 0.109 storms 0.098 tall 0.090 magnetometers 0.086 particles 0.085 magnetosphere 0.084 |
The Polar Aurora are natural displays of light in the sky that can be seen with the unaided eye only at night. An auroral display in the Northern Hemisphere is called the aurora borealis , or the northern lights ; in the Southern Hemisphere it is called the aurora australis . Auroras are the most visible effect of the sun 's activity on the earth's atmosphere. The beautiful and often eerie curtains of light in the night time sky have been observed by people for millennia. An aurora is an optical phenomenon |