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A sunspot, called AR3038, is growing extremely fast: its surface has doubled in just 24 hours! It is now about 2.5 times the size of Earth. According to Spaceweather.com, this sunspot has an unstable beta-gamma magnetic field, which could cause an M-class solar flare. However, this sunspot faces our planet directly, which could cause radio blackouts.
Solar flares occur when energy stored in twisting magnetic fields (usually above sunspots) is suddenly released. This release of energy then results in a burst of radiation across the entire electromagnetic spectrum, from radio waves to X-rays and gamma rays. It can also be accompanied by explosive jets of material, called coronal mass ejections. Some sunspot groups have a more complex magnetic structure than others and are more likely to lead to a solar flare.
Beta-gamma type sunspots are not the most active (the palm goes to delta type sunspots), but are still among the largest and most complex. In addition, it is oriented directly towards the Earth, which could have unfortunate consequences. This is because when a solar flare hits the Earth’s upper atmosphere, X-rays and ultraviolet rays ionize the atoms, making it impossible for high-frequency radio waves to bounce, creating a radio blackout.
More or less threatening events
These radio faults are classified (from R1 to R5) according to their seriousness; they touch the parts of the globe that are exposed to the Sun during the eruption. Solar flares move at the speed of light, taking about eight minutes to travel the approximately 150 million kilometers that separate us from the Sun.
The Earth has already been confronted with this type of event on several occasions. Two eruptions that occurred this spring thus caused level R3 blackouts over the Atlantic Ocean, Australia and Asia. In March 1989, the whole of Quebec was plunged into darkness for several hours following a powerful eruption that caused significant voltage variations on the electrical network of the Canadian province. Several other power grids across North America felt the effect of this storm and reported incidents.
The greatest solar storm our planet has ever experienced occurred in 1859. The phenomenon, called the “Carrington Event,” released energy equivalent to 10 billion one-megaton atomic bombs! This intense flux of particles strongly disturbed the telegraph networks of the time and caused numerous polar auroras, visible even in the tropics! If an event of the same intensity happened again today, needless to say, the damage would be considerable.
And we’ve already avoided the worst: a powerful coronal mass ejection passed through Earth’s orbit in July 2012… a week before our planet was in this precise place! Within a few days, we could have found ourselves in the 18th century. This eruption would indeed have largely disrupted the global electricity grid, air transport, telecommunications or any other electronic equipment.
Relatively sustained solar activity currently
Fortunately, AR3038 is not as dangerous. Currently, it is slightly north of the solar equator and Earth will be in its sights for a few more days. When a sunspot forms near the equator, it takes just under two weeks to get to the other side of the Sun — where it no longer poses a threat to us.
Despite its particularly rapid growth, this giant sunspot is not that worrying. If it were to produce flares in our direction, they would only be class M flares — the most common type of solar flare. These events typically cause brief radio blackouts affecting Earth’s polar regions, according to Spaceweather.com. Minor radiation storms can sometimes follow this type of eruption.
If particles from coronal mass ejections are absorbed by the Earth’s magnetic field, they instead trigger powerful geomagnetic storms. The flow of highly energetic particles from the Sun is channeled and propagates along magnetic field lines near the poles. These particles ionize the atoms in the upper atmosphere, which cannot remain in an excited state: they return to a lower energy state by releasing energy in the form of a photon, which creates magnificent colored auroras. .
But this flux of charged particles can also disrupt the magnetic field to the point of sending satellites crashing to Earth! SpaceX has already paid the price for this phenomenon, which led to the loss of around forty of its satellites in February. Thus, extreme geomagnetic storms could cripple our communications systems, including the Internet. The Sun is particularly active right now, because in 2020 we started a new solar cycle (each cycle lasts about 11 years). This activity is expected to increase steadily over the next few years, peaking in 2025. So far, the number of observed sunspots already significantly exceeds predictions.