Solar Flares are classified according to the amount of energy emitted by them per unit area. The classification is based on the energy released in the 1-8 Angstrom band.
Typically we have 4 major classes designated by letters B,C,M and X, with X being the most powerful of flares. Each of these letter classes is further subdivided into 9 subdivisions. So a X class flare can exist from X1 to X9, with X9 being the strongest flare.
||Flare Power (W/sq.m)
||1E-6 to 1E-5
||1E-5 to 1E-4
|| > 1E-4
The silence and boredom has ended. It seems that the yellow ball in the sky has decided to show that its not dead yet. After an unusually long hiatus, a large sunspot group just below the solar equator has formed. The spots recently released an M6 class solar Flare on Feb 13th at about 1738 UTC. This was followed up today by a X2 class flare released on Feb 15th on 0156UTC. Both flares have ejecta (coronal mass ejection) hurling towards earth, triggering geomagnetic storms over the polar regions of our planet.
X-Ray emission data from SOHO-CELIAS instrument, Wavelength from 1 t0 500 Angstrom
The flare originated from the sunspot group designated 1158. Astronomers predict that this feature on the sun isn’t done yet and there may be more fireworks soon. Besides the pretty auroras, flares like these can be annoying too. Strong flares have known to cause problems in power transmission lines, destroying sensitive electronics on board satellites and deep space missions.
19.02.2011: Another M Class Eruption, There is 75% chance of more outbursts soon