Aurora in Poland
On Thursday of May 9th, a series of five or six solar flares began on the Sun. A flare is a release of huge amounts of energy due to local changes in the magnetic field. The flare itself lasts from a few minutes to an hour and a half, depending on its intensity. In the case of more energetic flares, different phenomena often occur, such as protuberance eruptions or mass ejections. The latter are called coronal mass ejections (CMEs). It is a cloud of plasma, accelerated in the coronal region (the outer part of the sun’s atmosphere) and then ejected into interplanetary space.
Such events occur relatively frequently, but the sun throws CMEs in different directions and the probability of hitting the Earth with such an ejection is reasonably low. This time, however, the emission region was directed exactly towards the Earth. The Space Weather Prediction Center (SWPC) is an an American organization under NOAA. The SWPC has defined several scales for assessing the impact of solar weather on the Earth. In the case of geomagnetic storms, this is a scale from G1 (minor) to G5 (extreme). Storms G5 class are fairly rare - about 4 days on average during one eleven-year solar cycle. solar cycle. For solar radiation storms, the scale is similar and is labelled from S1 to S5. The last scale refers to radio blackouts and is has five levels - from R1 to R5.
Detailed definitions are available on the SWPC webpage.
A day later the SWPC issued a warning of a possible G4 geomagnetic storm. The plasma reached the Earth on May 10th. Of course, the weather in Poland could be counted on. There was full cloud cover over most of the country throughout the night, and the night was varied by numerous precipitation events.
On the other hand, there was luck on Saturday, May 11th. There were clear skies and the G4 alert still in effect. I decided to go to Mikoszewo, a small town on the coast, far from the Tricity agglomeration and its lights. It was a good choice. Above the horizon, greenness was visible to the naked eye. It looked a bit like the glow of a city visible from afar, only that it was greenish. This was more or less what I had expected.
I was completely unprepared for the second part. At an altitude of about 20-40 degrees there were gentle but clearly visible to the naked eye slowly undulating structures, the so-called pillars. They were pale and the pinkish-red colour was practically imperceptible, but they were clearly visible. Through this slow undulation there was no doubt.
I managed to take quite a few photos and some of them even look there somehow. I managed to put together a timelapse from some of them. Each frame is a single exposure of 6 seconds. The film is sped up six times. The slow undulation of the poles was visible to the naked eye. Below the timelapse:
