It's been an eventful year for sky-gazers in the northern U.S. The northern lights—a phenomenon that's normally limited to the Arctic circle—appeared above the country's northern border in March 2019, and then again at the beginning of September. If Michigan residents missed those two light shows in 2019, they'll possibly have another chance to catch the lights on September 27 and September 28, MLive reports.

What causes the northern lights?

The northern lights, or aurora borealis, are caused by particles from the sun reacting to molecules in our planet's atmosphere, "exciting" the gases and making them release photons. At northern latitudes, where magnetic energy and therefore solar energy is the strongest, the reaction is intense enough to produce colorful waves of light that are visible from the ground.

Occasionally, the sun wallops the Earth with enough solar particles to trigger this reaction farther south. The Space Weather Prediction Center projects a G1-G2 geomagnetic storm for this week, with the solar activity potentially producing auroras across most of Michigan.

When to see the northern lights

A G1 solar storm is expected to reach the planet on September 27. By September 28, experts predict it will have evolved into a G2-level storm. So if you plan to be in Michigan this week, Friday and Saturday are the best nights to see the lights. The northern lights are more common over the northern half of the state than the southern part, but in this case, nearly everyone in Michigan should have a shot at catching the spectacle. If it's rainy or cloudy in your area—as is projected for some places in Michigan this weekend—the lights will be harder to see. You will also be disappointed if you look up from Detroit, Grand Rapids, or any other metro area with significant light pollution in the state.

[h/t MLive]