Distribution of cool starspots on the surface of the red dwarf V647 Her

Photometric observations of the star V647 Her (M3.5V) obtained in 2022 at the 1.25 m telescope of the Crimean Astrophysical Observatory are analyzed. The presence of a low-amplitude variability in brightness of the star with a period of 20.69 d, found from observations in 2019, is confirmed; it is shown that as the brightness decreases, the star becomes redder. The observed nature of photometric variability is due to the presence of cool spots on the surface of the star and manifestation of rotational brightness modulation with a full amplitude of no more than 0m.05. We have performed a comparison of the photometric results obtained in 2019, 2022 and 2004. The zones of starspot concentrations in different epochs were determined from the analysis of phase curves. The distribution of spots has been maintained for 40–100 days. Starspot parameters were estimated in the framework of the zonal model. The temperature of the spots is 2700–2800 K. The area they occupied in 2004 is 15% of the total surface area of the star. According to the 2019 and 2022 data, it increases to 30%. The difference between the spottedness of the hemispheres caused by their seasonal redistribution is less than 2%.