A physicist explained the nature of the phenomenon over the capital: “All the most favorable conditions for a sky show came together”
On Monday night, the sky around the world shone with bright colors. Never before seen auroras flashed in almost all countries, including Russia, Ukraine, northern Kazakhstan, etc. This was facilitated by the ejection of solar matter from the active region of the Sun, which happened on April 21. About the reason for such an active light show, we talked with the head of the Center for Space Weather Forecasts, Deputy Director for Research at the Institute of Terrestrial Magnetism and Radio Wave Propagation of the Russian Academy of Sciences (IZMIRAN) Artem Abunin.
< p>So, a flare on the Sun with a power of M1.8 occurred near the group of sunspots number 23 283 last Friday at about 21.00 Moscow time and was accompanied by a powerful ejection. This zone was located right in the center of the solar disk and was heading towards the Earth with great speed.
— A geomagnetic storm on Earth was caused by the arrived solar substance on April 23 in the evening, in the afternoon, – clarifies Artem Anatolyevich. – According to the American gradation, there are five types of such storms, from G1 to G5, it belonged to the G4 class. This is a very high level, which, indeed, can be accompanied by bright auroral (from Aurora Borealis — northern lights) glows.
– We recorded a geomagnetic storm of the same class six years ago, in 2017. True, then it ended in a day, but this time it stretched for almost two days. Storm G4 was also with us a month ago – March 23-24, and a little earlier, in February. Only, for example, in the European part of Russia, the northern lights were not visible everywhere because of the clouds, but astrophotographers sent beautiful photos from the Urals and Kazan.
– The point is not only cloudiness, but also the time of the peak, the brightest period of the glow. The night of April 24 became sensational only due to the fact that at that time all the most favorable conditions for auroral aurora converged.
– The temperature has nothing to do with it: auroras occur at altitudes from 100 to 500 kilometers, – The temperature there has nothing to do with our thermometers. It's all about the geographical location: in high latitudes, auroras do happen more often due to physical laws. In fairly powerful events, the plasma causes a strong geomagnetic disturbance, which «descends» to lower latitudes.
In recent decades, geophysicists have observed such a phenomenon as the movement of the Earth's magnetic pole towards central Russia. If it does not stop, then by 2050 the pole point will not be the Arctic Ocean, but our Severnaya Zemlya archipelago.
— Depending on the height, the ionization of oxygen by charged particles occurs in different ways. Up to 200 km it appears green, at altitudes of 300-400 km – red.
– It is possible that we will find its echoes on the night of Tuesday, April 25.
– The maximum, according to various scientists, is expected from the end of 2023 to the end of 2024. This means that there will be more and more solar flares and associated geomagnetic storms.
– March and September are considered the most geoeffective months in terms of storm registration.
– We can predict such events if we see a suitable candidate spot for the Sun. In the next few days after this event, such «applicants» not observed.
Astrophotographers have noticed that most of the auroras look more noticeable in photographs than when observed with the naked eye. In normal mode, only the brightest events in the sky can be captured on a mobile phone, others require a professional camera, normal shooting mode and a slight color correction with contrast enhancement.