Solar Flares

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abuali
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Solar Flares

Postby abuali » 07 Dec 2010, 17:13

Image
courtesy: http://spaceweather.com/

As predicted, the a "mega-filament" of solar magnetism erupted on Dec. 6th, producing a blast of epic proportions. NASA's Solar Dynamics Observatory recorded the action as the 700,000-km long structure lifted off the stellar surface and--snap!!--hurled itself into space.

The eruption produced a bright coronal mass ejection (CME) observed by the STEREO-A spacecraft: video. Earth was not in the line of fire; the cloud should sail wide of our planet. Earth-effects might be limited to pretty pictures.

[extracted from wikipedia)
A solar flare is a large explosion in the Sun's atmosphere that can release as much as 6 × 1025 joules of energy[1] (about a sixth of the total energy output of the Sun each second). The term is also used to refer to similar phenomena in other stars, where the term stellar flare applies.

Solar flares affect all layers of the solar atmosphere (photosphere, chromosphere, and corona), heating plasma to tens of millions of kelvins and accelerating electrons, protons, and heavier ions to near the speed of light. They produce radiation across the electromagnetic spectrum at all wavelengths, from radio waves to gamma rays. Most flares occur in active regions around sunspots, where intense magnetic fields penetrate the photosphere to link the corona to the solar interior. Flares are powered by the sudden (timescales of minutes to tens of minutes) release of magnetic energy stored in the corona. If a solar flare is exceptionally powerful, it can cause coronal mass ejections.

X-rays and UV radiation emitted by solar flares can affect Earth's ionosphere and disrupt long-range radio communications. Direct radio emission at decimetric wavelengths may disturb operation of radars and other devices operating at these frequencies.

Image
Two successive photos of a solar flare phenomenon evolving on the Sun. The solar disk was blocked in these photos for better visualization of the flare


The frequency of occurrence of solar flares varies, from several per day when the Sun is particularly "active" to less than one each week when the Sun is "quiet". Large flares are less frequent than smaller ones. Solar activity varies with an 11-year cycle (the solar cycle). At the peak of the cycle there are typically more sunspots on the Sun, and hence more solar flares.
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Moonbeam
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Re: Solar Flares

Postby Moonbeam » 07 Dec 2010, 23:49

Earth-effects might be limited to pretty pictures.


Subhanallah! How the Almighty shows us His signs, and protects us at the same time! Imagine if even a spark landed on earth?!

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