As August 2024 set another 20-year high for sunspot numbers on the sun, recent solar flares have yet to top two solar flares from September 2017. One of these flares, which took place seven years ago on Sept. 10 2017, still holds further unbroken records.
September 2017 saw the declining phase of the previous solar cycle (Solar Cycle 24), which peaked in 2014. Following a period of lower solar activity, active region AR 12673 rapidly emerged onto the scene. AR 12673 produced a number of X-class solar flares, the most notable of which were Sept. 6 and Sept. 10, 2017.
