A rare aurora borealis hangs over the rocky shoreline of Peaks Island and Casco Bay Friday. Long Island is visible in the distance. Ben McCanna/Staff Photographer

The National Weather Service is projecting that the aurora borealis – the northern lights – will likely be visible in Maine on Friday and Saturday nights.

While it’s difficult to project where and exactly when the aurora borealis will be visible, experts recommend going to a dark area and watching the northern sky.

The aurora borealis – which appears as large flashes of color in the night sky – is caused by solar geomagnetic storms, a coronal mass ejection by the sun.

“The sun burps out a huge bubble of electrified gas that can travel through space at high speeds,” according to the NASA website.

The “view line” on Friday and Saturday includes many of the northern states and Canada.

The sun’s geomagnetic storms are the most severe in nearly 20 years, prompting the weather service to issue its first geomagnetic storm watch since January 2005.