On Tuesday night, an “energized solar wind” - as NOAA put it - produced conditions prime for aurora at northern latitudes.
NOAA’s Space Weather Prediction Center said a “moderate” (G2) geomagnetic storm hit the Earth. The brilliant aurora display occurred as the Earth’s magnetic field was optimally aligned with the incoming blast of solar charged particles, known as a coronal mass ejection (CME).
“When a CME arrives here at Earth, one of the most important aspects is the magnetic structure,” SWPC wrote on its Facebook page. “Sometimes the magnetic structure is so mixed up, it has little or no effect here at Earth, other times, like today, the structure or orientation is that which really effects Earth.”
Observing the aurora from Tromsø, Norway, Ole Salomonsen described a “mindblowing” scene for the website SpaceWeather.com:
This for sure was the strongest aurora so far this season. The magnetograms at the University of Tromsø went bananas! Tromsø is a city of about 70,000, so it has a lot of light pollution; even so, the auroras were clearly visible standing in the middle of the city. It was just sick!
Here are a few incredible photos that were posted to SpaceWeather.com’s gallery from the northern U.S., Canada and northern Europe: