The sun is seething with sunspots and popping with solar flares as it ramps up to its peak of activity this year. Combine that with the spring equinox that happens this month and we have the perfect recipe for strong displays of the Northern Lights that might make it down into Colorado skies.

The sun is a magnetic dynamo that erupts with powerful magnetic energy every 11 years and then settles down until the next eruption 11 years later. We are currently in Solar Cycle 25, the 25th 11-year cycle since careful records of sunspots began in 1755. The Space Weather Forecasting Center predicts that Solar Cycle 25 will reach its peak of solar magnetic activity sometime in 2024, most likely between January and October.

The number and severity of solar flares and coronal mass ejections, or CMEs, has been increasing in the last few months. CMEs are one of the main sources of charged particles from the sun that can trigger vivid displays of the Northern Lights, or Aurora Borealis, here on Earth.

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A recent study by NASA solar physicist David Hathaway confirmed that, over the last 75 years, March is the most geomagnetically active month of the year, followed closely by October. Auroras are nearly twice as likely in March and October as they are in the winter and summer months. Why?

Apparently, around the time of the equinoxes, when the Earth’s magnetic poles are neither tipped toward nor away from the sun, the sun’s magnetic field can link up with Earth’s to open up holes and let solar wind particles flood into our atmosphere, generating vivid displays of the aurora. Christopher Russell and Robert McPherron first explained this seasonal variation in the aurora in a pivotal 1973 study.

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So, where and when should you look for auroras this month?

Auroral displays usually fire up in the hours around midnight and first appear in the northern part of the sky, so find a dark location with a clear view to the north. In my experience from watching auroras in Colorado, an auroral display will begin as a green glow or arc low on the northern horizon. As midnight approaches, this green arc will brighten and expand upward from the horizon. Pay close attention, because when you see this green arc in the north, things are about to get exciting.

What happens next is called the “break up” stage. The green arc will literally begin to break up into a number of bright colored rays that reach up toward the zenith. This can happen very quickly, in as little as 30 seconds. Green and red are the most common colors seen in the aurora, but they can appear in almost any color of the rainbow. Sometimes, the rays will join together to form curtains that seem to wave and flutter in the wind. Before midnight, the rays and curtains move off toward the west, but after midnight, they change direction and move off toward the east. 

Soon, the rays and curtains will seem to all merge together into a continuous glow that slowly fades from view. A good display can last for 30 minutes or more. Sometimes, if you are lucky, the green arc will appear again in the north, signaling another break up.

As a side note, when I was working on my psychology degree at the University of Alaska Anchorage in 1995, I did a study on auroras and suicides. My hypothesis was that during times of maximum solar activity, the beautiful auroras that appear over Alaska might lessen depression and cause a subsequent decline in the suicide rate. What I discovered is that there was a significant correlation between the 11-year activity cycle of the sun and the suicide rate in Alaska, but in the opposite sense that I hypothesized. At times of maximum solar and auroral activity here on Earth, the suicide rate tended to rise with the solar activity. Mind you, this was only a correlation, not causation. To my knowledge, no one ever followed up on my study to find the underlying reason for that correlation. 

To maximize your chances of catching these dancing, colored lights, keep a daily eye on the NASA sponsored website SpaceWeather.com this month. It will provide aurora alerts and warnings of a pending aurora storm. Good luck! 

Jimmy Westlake is adjunct professor of physical sciences at Colorado Mountain College and former director of the Rollins Planetarium at Young Harris College in Georgia and the St. Charles Parish Library Planetarium in Luling, Louisiana. His column appears in the Steamboat Pilot & Today. For more, JWestlake.com.