Difference between revisions of "Flare"

From Glossary of Meteorology
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== flare ==
 
== flare ==
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<div class="definition"><div class="short_definition">A bright, [[transient]] event within the sun's [[chromosphere]] and [[corona]].</div><br/> <div class="paragraph">Flares produce enhanced [[emission]] at radio frequencies and in the [[ultraviolet]] and [[x-ray]] spectral  regions as well. They may also produce increased [[particle]] emission, often with [[ions]] of [[cosmic rays|cosmic  ray]] energies. Flares usually appear within minutes and fade within an hour. They are localized to  small areas (typically &lt;10<sup>-3</sup> of the solar disk) and usually occur within solar active regions.</div><br/> </div>
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<div class="definition"><div class="short_definition">A space weather term for a sudden eruption of [[energy]] in the solar atmosphere lasting from minutes to hours from which [[radiation]] and particles are emitted. Flares are officially measured and classified based on peak [[X-ray]] flux from 1-minute-averaged GOES X-ray Sensor (XRS) observations in the 1&#8211;8-angstrom passband. Classification generally begins at the "B" level (>0.000&#8201;000&#8201;1 W m<sup>&#8722;2</sup>) and increases by an order of 10 with each subsequent level to "C" flares, "M" flares, and "X" flares. Flare levels of B, C, and M are assigned multiplicative factors (1&#8211;9), which are appended to the letter (e.g., M4); flare levels of X are appended with a multiplicative factor from 1 to 20 (anything above 20 is estimated).</div><br/> </div>
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<p>Space Weather Prediction Center, 2018: Solar flares (Radio blackouts). Accessed 14 August 2018. Available at <nowiki>https://www.swpc.noaa.gov/phenomena/solar-flares-radio-blackouts</nowiki>.</p><br/>
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<p>''Term edited 14 August 2018.''</p>
  
 
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Latest revision as of 17:03, 14 August 2018



flare

A space weather term for a sudden eruption of energy in the solar atmosphere lasting from minutes to hours from which radiation and particles are emitted. Flares are officially measured and classified based on peak X-ray flux from 1-minute-averaged GOES X-ray Sensor (XRS) observations in the 1–8-angstrom passband. Classification generally begins at the "B" level (>0.000 000 1 W m−2) and increases by an order of 10 with each subsequent level to "C" flares, "M" flares, and "X" flares. Flare levels of B, C, and M are assigned multiplicative factors (1–9), which are appended to the letter (e.g., M4); flare levels of X are appended with a multiplicative factor from 1 to 20 (anything above 20 is estimated).

Space Weather Prediction Center, 2018: Solar flares (Radio blackouts). Accessed 14 August 2018. Available at https://www.swpc.noaa.gov/phenomena/solar-flares-radio-blackouts.


Term edited 14 August 2018.


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