Solar Flare classification origin

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Rules For
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Solar Flare classification origin

Post by Rules For » Thu Oct 01, 2020 8:37 pm

Does anyone know the origin of the A, B, C, M, X classification system for solar flares? I'm curious as to why it jumps from C to M and then to X (instead of A, B, C, D, E, for example). I figured there might be a historical explanation, like with the OBAFGKM stellar classification system, but searching online I've so far come up empty-handed.

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neufer
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Re: Solar Flare classification origin

Post by neufer » Fri Oct 02, 2020 2:42 am

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Rules For wrote:
Thu Oct 01, 2020 8:37 pm

Does anyone know the origin of the A, B, C, M, X classification system for solar flares? I'm curious as to why it jumps from C to M and then to X (instead of A, B, C, D, E, for example).
The A, B, C's are mere child's play.

M & X are warnings :!:

The Roman numeral M is 1000 ... times stronger than an A class :?:
The Roman numeral X is 10 ... times stronger than an M class :?:
Art Neuendorffer

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Chris Peterson
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Re: Solar Flare classification origin

Post by Chris Peterson » Fri Oct 02, 2020 3:19 am

neufer wrote:
Fri Oct 02, 2020 2:42 am
Click to play embedded YouTube video.
Rules For wrote:
Thu Oct 01, 2020 8:37 pm

Does anyone know the origin of the A, B, C, M, X classification system for solar flares? I'm curious as to why it jumps from C to M and then to X (instead of A, B, C, D, E, for example).
The A, B, C's are mere child's play.

M & X are warnings :!:

The Roman numeral M is 1000 ... times stronger than an A class :?:
The Roman numeral X is 10 ... times stronger than an M class :?:
I think that A and B classes came later. The original classification (using peak x-ray flux) was C, M, X. Which, with 100, 1000, 10 doesn't quite fit the Roman numeral hypothesis. Compact, medium, extreme? Common, medium, x-ray? Not sure, and not obvious.
Chris

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