On October 24, 2024, a significant X3.3-class solar flare erupted from sunspot AR3869, impacting radio communications across Asia, Australia, and the Pacific. The flare, which peaked at 03:57 UTC, resulted in radio blackouts at frequencies below 30 MHz.
The flare was accompanied by a suspected coronal mass ejection (CME), which may reach Earth in the coming days, potentially triggering geomagnetic storms and allowing the northern lights to be visible further south than usual. NOAA's Space Weather Prediction Center confirmed the solar activity, noting an asymmetrical halo CME observed shortly after the flare.
Sunspots, which are cooler and darker regions on the sun's surface, are sites of intense magnetic activity. These regions can grow significantly, sometimes exceeding Earth's size. The current solar cycle, which began in 2018, is characterized by increased solar activity, with this flare being the 11th most intense recorded since its start.
Previous observations indicated that the largest flare of this cycle, an X9.0, occurred on October 3. The frequency of such flares tends to increase during solar maximum, which occurs approximately every 11 years.
Solar flares release high-energy radiation that can disrupt the ionosphere, leading to radio wave absorption and blackouts, particularly affecting long-distance communication. The potential impact of the CME remains uncertain, but if it strikes Earth directly, it could enhance geomagnetic activity.
Scientists anticipate that the active sunspot group will return to a position facing Earth within the next two weeks, allowing for further monitoring and assessment of solar activity.