According to a solar physicist who was able to accurately predict that the solar maximum would arrive sooner, the peak of solar activity could have already started. However, this cannot be confirmed until long after solar activity calms down again.
Solar Maximum: the Peak of the 11-Year Solar Cycle
The solar maximum is the sun's most dangerous and active phase in the 11-year solar cycle. During this phase, the number of dark sunspots that coat the solar surface significantly increases. Consequently, they release more powerful and frequent solar storms. Some of these hit the Earth and lead to stunning auroras and radio blackouts.
This spike in activity is due to the magnetic-field lines of the Sun that become more tangled gradually. However, at some point in the solar maximum phase, the lines snap. This leads to a full reversal of the magnetic poles of the Sun.
After this, the Sun starts calming down. It then reaches the solar minimum phase eventually. This is when solar storms and sunspots almost fully disappear before the start of the next cycle.
Solar Maximum of Solar Cycle 25 Could Have Already Started
Initially, the solar maximum was predicted to start next year. However, the Sun may have already entered this solar maximum phase.
In 2019, the Space Weather Prediction Center (SWPC), which the National Oceanic and Atmospheric Administration (NOAA) runs, released a forecast for Solar Cycle 25, which is the current solar cycle that started that year. This forecast predicted that the coming solar maximum could be comparable in size to the previous cycle's relatively weak solar maximum. It also revealed that the solar maximum likely will not start until 2025.
However, scientists observed that the fiery behavior of the Sun did not align with these forecasts. Compared to what was predicted, sunspots popped up more frequently and released strong solar storms far more often.
In fact, in June, several researchers shared that the solar maximum could start earlier and be more active compared to what was initially suggested by forecasts.
Last October, the SWPC admitted that the earlier forecasts were off. They also unveiled updated predictions for the first time ever. These updates suggested that the solar maximum could start anytime between January and October 2024.
Months after this update, solar activity has gone up and down. A sharp peak was observed in December, while an odd lull was seen in January. This made it difficult to gauge the arrival of the solar maximum. However, a recent activity flurry in February suggests that the peak phase could have already begun.
Scott McIntosh, a solar physicist and the deputy director of the National Center for Atmospheric Research, who was one of the researchers who said that the peak phase could start earlier, expresses definite thoughts regarding how the Sun is entering its solar maximum. However, the official start and end of the solar maximum are difficult to distinguish. This is because the peak number of sunspots can only be pinpointed when they begin to drop. The official start of the solar maximum may remain a mystery for several years.
However, McIntosh explains that there could be another way to monitor the arrival of the solar maximum. This is done by checking the strength of the magnetic field of the Sun. In the period that leads to the solar maximum, the strength of the magnetic field at the solar poles decreases and eventually goes down to zero during the reversal of the poles. This can be monitored in real-time. McIntosh also explains that in the last few months, the strength of the polar magnetic field has been lingering around zero levels.
The solar activity lull in January implied that it was unlikely that a solar maximum had started. Because of this, McIntosh waited for a surge in solar activity before being convinced. This surge could have taken place in February, as X-class solar flares saw a major comeback.
If the solar maximum has really arrived, it may likely go on for a year or less, McIntosh explains. While sunspots will start decreasing, the number of strong flares will actually peak after this phase. This means that increased solar storms may be observed for years. If any of the strongest storms hit the Earth, they could affect infrastructure on the ground, lead to widespread auroras, and make satellites tumble back to the planet.
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