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In recent years, our Sun has been going through a highly volatile phase. Though still a year or more away from the next maximum, Solar Cycle 25 began in December 2019 and is already showing much higher solar activity than astronomers had predicted.As the Sun increases its level of activity, its surface develops with more sunspots, which are dark regions with intense magnetic activity, each with the potential to expel solar flares. Solar flares are large explosions on the surface of the sun that emit powerful energy which is then propagated through the universe. At high energy, solar flares eject a massive amount of charged particles from the Sun, known as coronal mass ejections (CMEs), which can produce powerful geomagnetic solar storms that disrupt Earth’s communications, electric power grids, navigation signals, and can also harm astronauts and satellites in space.In September of 1859, the largest solar storm to ever hit the Earth, known as the Carrington Event, wreaked havoc on international telegraph lines, setting widespread fires to telegraph stations, and ignited ultra-bright Auroras across the globe, some of which were visible as far south as the Caribbean. “Flares emit energy that propagates throughout the solar system at the speed of light, which is why the radio blackout occurred as soon as the flare was visible. Professor Von Fay-Siebenburgen of the University of Sheffield warned that a world increasingly reliant on technology was one more vulnerable to larger disruptive solar flares and more solar activity.”Since early 2022, we have seen more disruptive X- and M-class solar flares despite the Sun being a year or more away from its anticipated maximum. In February 2022, SpaceX reported losing 40 of its Starlink satellites to an extended geomagnetic storm. On April 19, 2022, the Sun produced its greatest solar flare in five years, an X2.2, which reportedly caused radio blackouts in Australia, the Western Pacific, and East Asia. A study published in 2019 found the chance of a Carrington Event-scale flare occurring before 2029 to be less than 1.9 percent. Nevertheless, astronomers like Dr. Avi Loeb, former chair of the Astronomy Department at Harvard University, think that the most recent substantial solar flares should serve as a warning that the world must be prepared for another solar storm event of great magnitude.
