Top: these panels represent Lomb–Scargle power for different rotation period power frequencies found in the CUTE and IUE datasets of Alpha Centauri A. The highest power is marked by the blue dashed line, which amounts to 15.9 days for the CUTE 2024 data. Based on the CUTE 2024 analysis, the highest peak between 15 and 20 days was found to be 17.5 days for the CUTE 2025 dataset and 18.75 days for the IUE dataset. Bottom: these panels represent the best period sinusoidal fit to the Mg II index data for the CUTE and IUE observations of Alpha Centauri A.