Photo/Illutration A red aurora is seen over Nayoro, Hokkaido, on Nov. 12, following intense solar flare activity. (Provided by Nayoro Observatory)

Spectacular red auroras appeared over Hokkaido on Nov. 12, triggered by a massive solar flare that erupted on the sun’s surface the previous day.

This was one of several intense explosions recorded this week, with the dazzling northern lights visible through breaks in the clouds at an observatory in Nayoro between about 6 p.m. and 11 p.m.

According to the National Institute of Information and Communications Technology (NICT), the flare released a massive burst of coronal gas directed toward Earth.

This can disrupt GPS signals, shortwave communications and satellite operations, though risks to everyday devices and human health are minimal.

Classified as an X-class flare, the most intense category on the five-level scale, the event followed several smaller X-class flares observed from Nov. 9. 

Solar flares typically occur near sunspots. Solar activity, which follows an 11-year cycle, has now reached a peak phase after hitting a period of minimal activity in December 2019 and steadily intensifying since.

The flare on Nov. 11 measured X5.1, making it one of the largest since an X9.0 flare in October 2024 that forced aircraft to reroute and spawned widespread auroras.

Experts caution that although the latest flares are lower on the numerical scale, their repeated occurrence could cause geomagnetic disturbances equal to or greater than last year’s.

The heightened solar activity also had global consequences with U.S. space company Blue Origin Enterprises LP postponing a rocket launch meant to ferry NASA spacecraft.