FAIRBANKS — Alaskans may see a spectacular aurora display this weekend after a strong solar flare aimed toward the Earth erupted late Alaska time Wednesday.

The geomagnetic storm was expected to reach Earth on Friday night or tonight and could spark increased auroral displays throughout the weekend, according to the Geophysical Institute’s aurora forecast and spaceweather.com.

Weather permitting, the aurora could be seen as far south as Des Moines, Iowa, and Chicago.

NASA reported on its website that the flare was also associated with an Earth-directed coronal mass ejection, a different type of solar event that also sends solar particles into space. Those can reach the Earth one to three days later, according to NASA.

NASA reported that its experimental research models show that the coronal mass ejection began at 3:36 a.m. Eastern Daylight Time on Thursday — 11:36 p.m. Alaska Daylight Time on Wednesday — and left the sun at more than 600 miles per second.

“This is the strongest flare seen so far in 2013,” a notice on NASA’s website says. “Increased numbers of flares are quite common at the moment, since the sun’s normal 11-year activity cycle is ramping up toward solar maximum, which is expected in late 2013.

“Humans have tracked this solar cycle continuously since it was discovered, and it is normal for there to be many flares a day during the sun’s peak activity.”

Contact the newsroom at 459-7572.