Last week, a massive hole in the Sun’s atmosphere led to a severe geomagnetic storm that put satellites on high alert and delivered Northern Lights down to very low latitudes. And now there is another one. Forecasting expects another increase in solar wind to arrive towards the end of the week, providing another chance for spotting these magnificent aurorae.
The coronal hole is a region in the Sun’s corona – its outer atmosphere – which is cooler than the rest due to open unipolar magnetic fields. The magnetic fields are what allow the solar wind – the stream of charged particles escaping the Sun – to move away more freely and hence more quickly. And this might lead to an increase in geomagnetic activity.
Forecasting from the University of Alaska Fairbanks Geophysical Institute shows an increase in geomagnetic activity for both Thursday and Friday this week. However, the National Oceanic and Atmospheric Agency has yet to announce forecasting for those days in case a minor geomagnetic storm will take place. A clearer idea of the effect of this hole on our planet will come in the next few days.
So, it might be worth keeping an eye on it if you are keen to go aurora hunting (and photographing) in a few days!