With the entry of autumn, starting from the equinox day that fell on September 22, and the sun’s rays began to recede slowly from the outskirts of the northern hemisphere, the night begins to return to those areas that will lose the sun’s rays for long days, perhaps up to 6 months. In the areas of the pole.
And in the absence of the sun, the night prevails for a longer and longer period, and the manifestations of winter begin to emerge little by little, the weather cools very quickly, the rains fall, and the earth is covered in a white coat that lasts for weeks and months.
With this long night, the inhabitants of the extreme northern countries such as Norway, Iceland, Sweden, Finland, Canada and northern Russia will return to receive those brightly colored heavenly displays known as the aurora borealis or the northern lights.
Almost every night, they have the opportunity to see some of these shows, with different brightness and length of appearance, according to the solar activity cycle that repeats every 11 years.
The sun .. the source of all lights
The reason for lighting the day, dusk, twilight, moon, planets and comets is due to sunlight, all of which are illuminated by direct sunlight.
But the aurora borealis light differs from all of that, as it is a trace of solar energy interacting with the upper atmosphere of the Earth in the form of charged particles that ionize the abundant oxygen and nitrogen atoms there, and emit from them colors that vary in the diversity of the ionized atom, including yellow, blue, green, red, pink and violet.
The Arab history books recorded many events of the appearance of the aurora borealis displays in Arab regions, reaching Yemen downward at the 15th latitude north of the equator, and this means that the aurora borealis was not at that time limited to that patch located between latitudes 60-80 degrees north, as it is When twilight appears in its normal days.
The aurora borealis appeared over Germany on January 1, 1203 AD, and was seen in France in March 1204 AD, and in the two scenes, great columns appeared interspersed with flaming flames, and the sky was red.
As for the Arab evidence compiled by the Iraqi astronomer, Dr. Wafiq Shaker Rida, the aurora sighting came from the history of Yemen, where the Yemeni historian Yahya bin Al Hussein, author of the book “The Purpose of Wishes in the News of the Yemeni Country,” mentions his text:
On Safar of this year 600 AH (around October 3, 1203 AD), a verse of the splendid ayat of God appeared, which was a red one that occurred after sunset, whose light prevailed in the morning light, and that was in the mountains of Yemen and its east, and in Tihama a severe darkness that lasted 3 days And the jurist Ahmad bin Muhammad al-Mahli, a teacher in Dhi Marmar, narrated on the authority of a man from Zabid that this darkness occurred on Wednesday night, after the moon had risen, and it spread over the country and continued until Friday, then it ended.
Likewise, in Japan, history books recorded the appearance of auroras in 671 AD, a red color that filled the sky with redness.
Current solar activity cycle
As it is known, the sun passes every 11 years in a cycle of activity determined by sunspots appearing on its surface, so with the increase in the number of these spots, the cycle becomes active and dangerous at times, and it also causes the frequent and uninterrupted appearance of the aurora shows.
Modern history (during the past 200 years) has not recorded an observation of the aurora from medium latitudes, nor at low, of course.
Climate scientists expect that the current 25th sun cycle – which has just started in 2020 – will be one of the quiet cycles that may play a role in changing the climate, in terms of its impact on the greenhouse effect, melting ice caps, and then the rise in water levels for coastal cities.
And because it is still in its infancy, it cannot be assured of its calmness or activity except through extrapolation based on the shape of previous solar cycles.
And if the session shows something unusual, it will be reflected directly on the sky, so that some people will be able to see the picturesque aurora displays.