Major far side coronal mass ejection

Sunday, 23 July 2017 - 11:05 UTC

Major far side coronal mass ejection

An absolutely massive far side coronal mass ejection can now be seen on both STEREO and SOHO coronagraph imagery.

The coronal mass ejection as captured by the SOHO/LASCO C2 coronagraph. 

it is a very fast and dense symmetrical full halo coronal mass ejection. A very impressive event indeed but do note that it came from the far side and the plasma cloud is directed away from us. There is no chance that it will arrive at Earth. It is very rare we see such fast and nice halo eruptions and if it would be earth-directed these kind of plasma clouds could easily cause severe to extreme geomagnetic storming.

Source of this massive plasma cloud looks to be a solar flare from old sunspot region 2665 as you can see on our header image at the top of this page. We do not have a satellite like the GOES-series that monitors far side solar X-ray emissions but using STEREO imagery it looks like this was at least a high M-class solar flare, perhaps an X1 event.

Amazing to look at, but (un)fortunately not aimed at our planet!

Current data suggest that it is not possible to see aurora now at middle latitudes
G2 - Moderate geomagnetic storm
Observed Kp: 6
The solar wind speed is currently moderately high (605.6 km/sec.)

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Today's space weather

Auroral activity Minor Severe
High latitude 25% 35%
Middle latitude 5% 1%
Predicted Kp max 4
Solar activity
M-class solar flare 25%
X-class solar flare 1%
Moon phase
New Moon


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