People living in the southern hemisphere might had a chance to enjoy a light show as solar wind light passed through the upper atmosphere of the Earth. The auroras could be seen in North Dakota, Minnesota, Maine, Michigan, Alaska, central Canada, certain fractions of Wisconsin. Northern Russia, the Shetland Islands and Scandinavia also has a chance to witness the lights in the sky.
If you are curious about the areas where the aurora can be spotted you should know that the National Weather Services’ Space Weather Prediction Center released a map with the all the regions that might see the Aurora Extent. They also have more information available on the SWPC aurora model.
The auroras were caused by a solar storm. A coronal hole is what caused it and that hole represents a patch in the sun’s atmosphere where the outermost layer, as well as the corona, are significantly thinned. Coronal holes are nothing to worry about as they are quite common, and NASA’s Solar Dynamics Observatory observed three coronal holes from April 3 to April 6.
These holes are what allows solar wind to escape, and from there it can make its way to the Earth atmosphere, like it happened in this situation. However, there is no reason to worry about it, as it does not represent any danger.
A minor storm
This solar storm was a G1-class storm, which means that it is not dangerous at all, although it might create some problems with satellite communications. The most severe solar storm would be a G5 storm. The last powerful geomagnetic solar storm took place in 1859, but if one happened nowadays the consequences could be more serious, as we are quite dependent on technology.