BEIJING, Oct. 10 (Xinhua) -- Geomagnetic storms are expected to occur in the next three days, with possible aurora sightings over northern China, according to China's National Center for Space Weather on Thursday.

The center says that Earth could experience a strong geomagnetic storm from Thursday evening to Friday evening, and if no new solar activity occurs, a small to moderate geomagnetic storm is possible on Saturday.

The forecast followed a series of intense solar flares earlier this week, including two powerful X-class eruptions on Tuesday and Wednesday. Solar flares are rated based on their strength, with A-class being the smallest, followed by B, C, M and X as the most potent.

These storms generally do not affect human health but usually bring with them the phenomenon of auroras.

Due to the upcoming geomagnetic storms, colorful auroras will be observable from Thursday night, the center said.  ■