A huge dark hole has appeared on the surface of the Sun, spewing powerful streams of solar wind directly onto the Earth. Scientists note that the size and orientation of this time gap is without precedent for the current solar cycle.
Photo: openverse by NASA Goddard Photo and Video is licensed under CC BY 2.0
The coronal hole, known as a giant dark spot, has been forming near the solar equator since December 2 and reached a maximum width of about 800,000 kilometers within 24 hours, Spaceweather reported. com. Starting on December 4, it is aimed directly at Earth.
This phenomenon, known as a coronal hole, occurs when the magnetic fields holding the Sun suddenly open up and the upper layers of the Sun are blown away as the solar wind. NOAA says coronal holes appear as dark spots due to their lower temperature and density compared to the surrounding plasma. This is similar to the phenomenon of sunspots, but unlike them, coronal holes are not visible without ultraviolet light.
Radiation flows from coronal holes are much faster than the normal solar wind and often cause geomagnetic storms in the Earth’s magnetosphere. The latest coronal hole, which emerged in March, caused the most powerful geomagnetic storm in more than six years.
Experts assumed that the current hole could cause a moderate geomagnetic storm, however, according to data Spaceweather.com the solar wind turned out to be less intense than expected, and the resulting storm is still limited to weak severity (G1). But auroras may still be visible.
According to NOAA, it is unclear how long the “hole” will be in the Sun, but previous coronal holes have existed for more than one solar revolution, that is, approximately 27 days. However, in the near future the “hole” will turn away from the Earth.
Solar activity is intensifying this year as the Sun approaches the explosive peak of its approximately 11-year solar cycle known as solar maximum. However, the new coronal hole does not appear to be associated with this increase in solar activity.
NOAA stresses that coronal holes can appear at any point in the solar cycle, although they are more common during solar minimum. However, in this case, it remains a mystery how such a massive hole appeared near the equator during a period close to solar maximum.
There have also been other signs of increased solar activity in recent weeks. On November 18, a giant giant appeared on the near side of the Sun. “sunspot archipelago”, consisting of at least five different groups of sunspots, and several solar flares have occurred since then. November 25 eruption “fire canyon” resulted in a coronal mass ejection, which then collided with the Earth, causing rare orange auroras. On November 28, a “nearly X-class” solar flare occurred, producing a CME that caused a geomagnetic storm and auroras at lower latitudes.
These latest signs of activity likely indicate that solar maximum is approaching. In October, scientists revised their solar cycle predictions and now expect an explosive peak in early 2024.
We previously reported that another storm on Earth caused an explosive solar flare of “almost X-class”.
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