Faint halo coronal mass ejection

Wednesday, 8 May 2019 15:47 UTC

The coronal mass ejection became first visible yesterday during the early hours of 7 May. Source of this plasma cloud is continues activity in sunspot region 2740 but a specific event is hard to pinpoint. However, with the help of STEREO Ahead we do know that this coronal mass ejection is a front side event from a source facing Earth.

The coronal mass ejection is really faint and only really shows itself with the help of difference imagery. Below you will find an animation of such imagery from SOHO/LASCO C2. You can see the faint outline of an expanding halo which signals that this plasma cloud could have an earth-directed component. The cloud is faint and slow so do not get your hopes up too much but it will be an interesting event to follow. Most of the cloud is heading well north-west and only a faint outline can be seen expanding towards the south east and with a speed of about only 400km/s, the plasma cloud is not much faster than the ambient solar wind. A glancing blow is possible from this event but we should at most expect a minor increase in geomagnetic activity at Earth. Geomagnetic storming is very unlikely. With a speed of about 400km/s, the cloud will likely arrive at Earth somewhere late on 10 May which would be this Friday or early on 11 May.

Animation: A faint halo coronal mass ejection as seen by the SOHO/LASCO C2 coronagraph instrument.