Northern lights are often difficult to predict

The solar wind itself is not constant and because the sun goes through periods of high and low activity approximately every 11 years (a solar cycle), the solar wind fluctuates.

Sometimes the Sun spits out a lot of energy in a solar storm called a coronal mass ejection, or CME. When these occur, the solar wind rushes toward Earth with more energy. This energy then interacts with the Earth's magnetic field, disrupting its regularity and reconfiguring it. Cracks in the field open and close as the Sun's and Earth's magnetic fields combine.

When the various elements in Earth's atmosphere fluoresce, they display a dazzling display of colors of green, red, purple, pink and even blue known as the Northern Lights or Aurora Borealis (the Southern Lights or Aurora Australis in the Southern Hemisphere). . NASA's Magnetospheric Multiscale Mission was launched nearly a decade ago to observe electron reconnections in the magnetosphere and help us better understand and predict this space weather.

With that in mind, let's get back to this weekend's aurora forecast. When gusty winds are forecast during a storm, sometimes the gusts are stronger or weaker than predicted. These gusts of wind occur at relatively irregular intervals during a storm.

For example, no one can predict that there will be gusts of wind in a storm at 11:07 a.m. We often say that the strongest gusts are likely to occur in a specific time window, but there is still something random. After a CME occurs, space weather researchers use various tools to predict when these solar wind gusts are likely to interact with the magnetosphere, but which part of the magnetosphere is most charged and the intensity and location of geomagnetic storms and substorms are often difficult to detect.

Additionally, a storm could be occurring over another part of the planet while we are in daylight, or cloud cover could be blocking the view of a storm overhead.

I first saw the Northern Lights in the summer of 1981 in Maine. It's a sight I've witnessed several times since, and it never fails to disappoint. Keep an eye on social media this weekend and be ready to check. If you're lucky, you might even be able to witness one of nature's magnificent spectacles.

But of course no promises.