Northern Lights, also known as Aurora Borealis, are generally active due to a solar phenomenon known as solar storms or coronal mass ejections (CMEs).
These storms are large expulsions of plasma and magnetic field from the sun’s corona. When the charged particles from these storms reach towards the Earth, they interact with the Earth’s magnetic field and cause it to change and move.
As the particles enter the Earth’s atmosphere near the North and South poles, they collide with gas particles, which then results in the breathtaking display of lights we see as the Northern or Southern Lights.
The level of activity of the Northern Lights is directly related to the activity of these solar storms. If there’s increased solar activity, we’ll likely see more of these lights. Sometimes scientists can predict an increase in this activity based on observed sunspot patterns and solar flare activity.
Therefore, if Northern Lights are expected to be visible across parts of the U.S this weekend, it’s probably because there’s an increase in solar storm activity at the moment.