However, during a period of low solar activity, this is not an out of the ordinary phenomenon
Experts from the American aerospace agency NASA said that they recorded a coronal hole on the Sun, occupying one sixth of the entire surface of the star. Researchers from the Solar Dynamics Observatory also presented video footage showing the unusual phenomenon "up close."
Coronal holes are regions of the solar corona in which the temperature and plasma density are reduced. Although "holes", in the strict sense of the word, they, of course, are not, in the X-ray images, they really look like dark holes on the surface of the star. Although such huge coronal holes cannot be called a frequent occurrence, they are not something supernatural or truly dangerous for the Earth, experts say. According to them, sometimes the size of such areas can reach a quarter of the entire surface of the Sun, and they can not disappear for weeks or even months, writes the newspaper Huffington Post
However, coronal holes emit a considerable amount of solar wind, which, as in the case of solar flares, can cause magnetic storms on Earth, interruptions in the operation of some electrical devices and communication problems, as well as, in some cases, aurora …
Scientists explain that coronal holes are typical for periods of decreased solar activity. The fact that this stage had really begun became known in June - this was evidenced by the disappearance of all sunspots from the surface of the star. The cycle of fluctuations in the activity of the Sun lasts about eleven years, and the nearest minimum, according to astronomers' forecasts, will be reached in 2019-2020. Before that, the periods of absolutely "pure" Sun will repeat more and more often, and last longer and longer.
Dmitry Erusalimsky