The solar cycle is a periodic phenomenon where the sun undergoes an activity cycle approximately every 11 years, transitioning from a quiet phase to a highly active one. During the quieter phase, sunspots and solar flares are minimal. As the cycle progresses, solar activity escalates, peaking at what is known as solar maximum. This period is characterized by an increase in sunspots, solar flares, and coronal mass ejections—significant bursts of plasma and magnetic fields into space.
The current solar cycle, referred to as Cycle 25, is surpassing scientists' expectations. In May 2024, solar activity reached such intensity that it triggered the strongest geomagnetic storm in two decades. This phenomenon even allowed observers in areas with minimal light pollution to witness the aurora borealis. Earlier this month, another powerful solar storm impacted Earth. Although these events are spectacular, scientists indicate that such occurrences are not unusual during solar peaks. Lisa Upton, chief scientist at the Southwest Research Institute and co-chair of the international Solar Cycle Prediction Panel, stated, 'While we have observed several significant storms, they still fall within what we can expect during a maximum phase.' NASA and NOAA anticipate more of such storms in the upcoming months.
The increase in solar activity not only influences the formation of auroras but also poses risks to various technological systems on Earth. GPS navigation, radio communications, and electrical grids may experience disruptions due to intense bursts of solar radiation and magnetic energy. Astronauts in space could also be affected by heightened solar activity. With NASA planning to send astronauts back to the moon in the coming years, understanding solar peaks becomes crucial.
NASA and NOAA are currently preparing for these events. In December this year, NASA's Parker Solar Probe will make its closest approach to the sun to date. This mission is vital for enhancing our understanding of solar weather. Launched in 2018, the probe has passed by the sun multiple times, gradually getting closer. In 2021, it flew through the sun's corona, the superheated 'atmosphere' surrounding our star. It is also the fastest human-made object in history. When the probe reaches its closest approach to the sun in 2025, it will achieve a speed of 690,000 kilometers per hour.