We are still far from the year's end, yet we already received an application for the most impressive solar event of the year. A relatively modest C3 flare near the small sunspot group NOAA 2542 turned out to be very impressive in imagery taken in the more energetic EUV (extreme ultraviolet) passbands. Lasting 2 hours and 14 minutes, it was also a long duration event. An enhancement in the energetic particle flux was observed, but the proton event threshold was not reached.
This event pretty much got it all. Double ribbon flare, coronal dimming, arcade (series of post-flare coronal loops), supra-arcade downflows,... the list is long with this one! There was also a partial halo associated with it, but not directed to Earth. Above a picture near the x-ray peak (16:03UT) in white light (SDO/HMI; about 6000 degrees; "solar surface") and in EUV (SDO/AIA 094: "corona" or hot outer solar atmosphere at a temperature of several million degrees). Underneath (16:55UT) a comparison of the lower atmosphere of the Sun (AIA 304; around 80.000 degrees) again to the "hot" AIA 094.
A movie was compiled in which images from the various passbands are compared to each other. The movie ends with a comparison of all 4 EUV passbands: in one clip they are nicely separated from each other, in the other clip they are combined (one image layer on top of the other). Besides the AIA 304 and AIA 094 images, also AIA 171 (temperatures around 700.000 degrees) and AIA 131 (multi-million degrees) were used.
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