On the evening of November 5, the aurora was visible from almost the entire territory of Ukraine. These phenomena are considered “rare” for our latitudes. But this year we already had the opportunity to observe one of them on April 23, and astronomers noticed that, at least until the end of 2024, their frequency and intensity would increase as solar activity increased. And so it happened.
The fact is that flares on the surface of our luminary are the cause of auroras. During them, numerous charged particles (solar wind) are thrown into space, which begin to intensively bombard the atmosphere of our planet, interacting with its gases and causing their atoms to emit light in the visible range of the spectrum. Under normal conditions, the Earth is protected from them by a magnetic field, but when there are too many such particles and their energy significantly exceeds the average, they “break through” into the atmosphere deep enough, and the intensity of their glow allows it to be noticed with the naked eye.
Most often, auroras are green. This is how molecules and atoms of atmospheric gases, primarily oxygen, glow at an altitude of 80–300 km after a collision with solar wind particles. If there are enough of these particles, the frequency of collisions also increases at high altitudes — from 300 to 500 km. They have other energy characteristics, so from the Earth we see a red color. In fact, the remnants of the atmosphere in this altitude range “glow” constantly, but their glow is too weak to be noticed by the eye (in the dark, its sensitivity to the red part of the spectrum decreases). During the event on November 5, red color prevailed in the sky, although under successful observation conditions it could be noticed that the lower part of the “light pillars” was yellow and greenish.
The conditions for the visibility of the aurora are determined by the geomagnetic activity index, which is regularly published by the largest solar observatories. If it exceeds 5, we can expect that the auroral oval (the ring-shaped zone of visibility of the aurora) will “touch” the north of Ukraine. According to the predictions of heliophysicists, on November 6 and 7, it will reach 6 —but with quite significant daily fluctuations. This means that today and tomorrow, from the territory of Ukraine, with a high degree of probability, it will be possible to see the “celestial show” again. It is enough to check the northern part of the sky from time to time after dark in cloudless weather.
In the coming years, it seems that auroras from the category of “rare phenomena” will turn into something quite familiar for us, as they have long been for the northern part of Europe, Asia and a significant part of North America. Therefore, do not worry about the fact that the next glow threatens us with something; we already have enough reasons to worry, and much more significant ones.
The solar flare, as a result of which a huge canyon is formed on the surface of our luminary, has no direct relation to the current aurora.
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