Coronal mass ejection arrival

Thursday, 31 December 2015 - 00:27 UTC

Coronal mass ejection arrival

It took a little while but the anticipated coronal mass ejection has finally arrived. It hit ACE at 00:03 UTC which is less than an hour from our predicted arrival time.

This coronal mass ejection came from an M1.8 solar flare that took place on 28 December. Be sure to read our previous news updates if you wish to know more: here and here.

Impact analysis

We are going to be honest here, it is looking like a weak impact. The strength of the IMF went to 13nT which is not that high and the solar wind speed only got to just over 400km/s. We do have to note that we write this just minutes after the CME hit ACE which means it is still early and a lot can happen in the hours ahead as the inner plasma cloud itself passes our planet.

it isn't looking all that great for geomagnetic storming conditions right now as the direction of the IMF is northward as well but do keep an eye on the data as much can change in the hours ahead! Good luck!

Image: ACE solar wind and IMF data at 00:23 UTC just minutes after the impact.

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