Solar Flare Season

On Friday, May 10, almost every corner of the world was treated to a sight normally exclusive to Earth's frozen poles: the Aurora Borealis, or long, trailing patches of color swirling across the night sky. The Aurora Borealis, otherwise known as the “Northern Lights,” occurs when energized particles from the Sun collide into the Earth’s atmosphere at up to 45 million miles per hour. Each solar particle in this stream of solar wind is in the plasma state, a fourth type of matter consisting of charged particles like electrons, protons, alpha particles, heavy ions, or isotopes. The particles' interactions with Earth's magnetic field lines cause them to move along the lines to either Earth's north or south pole. The flow of solar particles is known as solar wind, which originates from the Sun's corona. Therefore, most of the Aurora Borealis that occur are at Earth’s geographic poles.
The corona is the outermost layer of the Sun, and is responsible for ejecting solar wind, but the actual particles come from deep inside the Sun. First, energy from nuclear fusion, the combination of small nuclei into bigger nuclei, is generated in the Sun's innermost core. Next is the radiative zone, where the energy produced slowly moves outward. Above this layer is the convection zone where the energy drives the motion of heated and cooled gasses in congregated convection-current patterns, known as convection cells. Outside of it is the chromosphere where the Sun's magnetic field lines are located; these fields restrain charged solar plasma. The plasma is eventually transitioned to the outermost corona, which consists of extremely hot ionized matter, and occasionally, some outflowing plasma gets ejected through the corona out into space; hence, solar wind. The solar particles in the plasma escape the Sun’s immense gravity, due to high temperatures in the corona generating increased levels of kinetic energy, which results in extreme acceleration since kinetic energy and acceleration are positively correlated. This aura of particles surrounding the Sun is known as the Sun's coronal magnetic field.
May 2024 was the first time since February of 1872 (time of the Carrington Event, history's largest solar storm) that the Aurora Borealis was observed near the equators. Astrologists have identified the reason: recent solar winds are more powerful and frequent than normal. Their interactions with the magnetic field caused them to create geomagnetic fields in Earth's atmosphere, which has prompted scientists to wonder about the causes behind increasingly powerful and prevalent solar flares that reach Earth. So far, scientists have noted an increased number of coronal mass ejections (CMEs). These mean that instead of the constant stream of plasma (solar winds), the Sun occasionally releases a large amount of particles in a single ejection. This occurs when the Sun's magnetic field lines in the lower corona become overly twisted and start unwinding into a more relaxed, straight configuration. Since magnetic fields result from moving charged particles, these moving lines promote an expulsion of sudden magnetic force from the sunspots that propel a large amount of plasma outward in the form of a CME, creating a moving solar storm. Sunspots are essentially concentrated magnetic flux lines (which indicate the state of the Sun's magnetic field). The solar storm can reach speeds of 8 billion miles per hour, and oftentimes, it is directed at the Earth. CME interactions with Earth's magnetic fields generate entire geomagnetic fields in Earth's atmosphere, thereby leading to increased coloration absorbed. This occurs when Earth's magnetic flux lines bunch up together to deflect the magnetic field carried by the solar wind, and as Earth's field keeps deflecting, the solar particles travel along Earth’s flux lines, tracing them back to the poles. These particles (composed of protons and electrons, primarily) collide with the oxygen and nitrogen of Earth's atmosphere, transferring over their energy to Earth's particles. The oxygen and nitrogen have then been excited enough to release photons, and the different colors we see during an Aurora Borealis arise from the different wavelengths of the photons released.
The recent spike in CMEs is attributed to the solar magnetic activity cycle, known as the solar cycle, which has a length of 11 years before repeating. Every 11 years, the Sun's magnetic poles switch places. Scientists quantify sunspots in order to track the cycles. The maximum number of sunspots (solar maximum) appear at around the 5.5-year-mark, before returning to the “quiet phase” with minimal sunspots (solar minimum). When there are more sunspots, the magnetic fields increase, and when the magnetic fields of each sunspot come into contact with each other, energy is released as solar flares that are ejected into space. The Sun’s current solar maximum is expected to occur in July 2025 with a maximum of 115 sunspots. Thus, from 2024 to 2025, scientists expect only an increase in solar flares, leading to more frequent geomagnetic/solar storms.
As of May 9, the Earth experienced a level G5 geomagnetic storm level—the highest along the levels of geomagnetic storms—because at least five CMEs crashed into Earth's magnetic field, along with the regular solar flares. The storms have affected satellites, radio operators, and power grids, causing power outages in many parts of the world, such as Ohio, Texas, and Michigan in the US. The last time Earth faced a G5 storm was in October 2003, where the majority of South Africa's transformers, devices that alter input voltages, were damaged, leading to irregular and dangerous voltages across the country. As a result of these catastrophic risks, federal agencies are trying to address the threat solar storms pose to power grids. Some are building easily deployable transformers that can be installed anywhere when there is a sudden blackout. Since buying equipment to protect large transformers would be too costly, some utilities are building capacitor banks which absorb energy and can act like batteries. Other facilities rely on forecasting solar storms in advance for power grids to shut down before getting bombarded by solar rays.
As the Sun is set to reach the peak of its solar cycle in 2025, there is a high probability that we will witness heightened solar activities over the next few years. However, astronauts predict the risk of our world without the internet for weeks or months afterwards. If such happened unexpectedly, it would yield catastrophic results for daily life, not to mention the economy; in fact, economists predict that just 24 hours without power in NYC would cause the city to lose $1 billion. Therefore, over 27 programs are working to try to prevent a power outage, primarily by keeping transformers in reserve. Transformers take electrical power from a central source and amplify or decrease voltage (depending on the circumstance), providing us with home electricity. To make transformers readily accessible, the Department of Homeland Security has established a Recovery Transformer program, a system of creating easily assembled transformers for rapid, temporary use, in case of a blackout. Additionally, the DOE (Department Of Energy) has taken precautions by creating a reserve of easily transportable transformers for emergency use. Since humans cannot unfortunately control the Sun's coronal ejections, the best we can do is prepare for the effects of a potential geomagnetic storm and simply enjoy the gorgeous view from the comfort of our own cities, instead of flocking to the Artics for a glimpse of this scientific phenomenon.