Example of GOES X-ray plot from Jan. 19-21, 2005
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This plot shows solar X-ray flux over a three day period.
The peaks represent solar flares.
GOES X-ray plots show data in two wavelength bands (0.5-4.0 Ångströms (Å) and 1.0-8.0 Å)
and usually contain data from more than one spacecraft.
The left axis gives the X-ray flux in Watts m-2,
while the right had axis gives the letter designation for each order of magnitude.
Each flare is given a GOES classification consisting of this letter and a number,
assigned according to the peak of the 1.0-8.0 A emission.
The letter designates the order of magnitude of the flare:
|
Class |
Peak (W m-2), 1 - 8 Å |
| B |
10-7 - 10-6 |
| C |
10-6 - 10-5 |
| M |
10-5 - 10-4 |
| X |
> = 10-4 |
The number is the multiplier needed to specify the exact peak flux.
An M2.4 flare has a peak flux of 2.4×10-5 W m-2.
There are two X flars in the plot on the left, one on Jan. 19, the other on Jan.
20. The next brightest flares shown in the plot are all M flares.
The flare emission is superimposed on a background made up of many events. This background
goes up and down dramatically with the solar cycle.
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