Advances in high-resolution spectroscopy have pushed radial velocity (RV) precision to 10 cm/s, but stellar magnetic activity remains a major limitation, mimicking or obscuring planetary signals. No definitive method has fully disentangled these effects. In this work, we successfully model the RV and photometric variations induced by stellar activity–specifically

spots and faculae–using the new SOAP4.0 code. Surface features from HMI and AIA SDO images are identified using different methods, applied to simulate their impact, and compared with HARPS-N and VIRGO/SPM solar data. After subtracting the modeled activity signal to the observed solar data, the residuals reach ~m/s precision, approaching the 80 cm/s granulation limit identified by Meunier et al. (2015). This precision is constrained by incomplete physical modeling, which, with further refinement, could enable the 10 cm/s precision needed to detect Earth-like exoplanets. Furthermore, we demonstrate that different methods for identifying active regions lead to significantly discrepant results, greatly influencing the resulting RV precision. To enhance our understanding of stellar activity, the Paranal solar ESPRESSO Telescope (PoET) has been developed. This telescope, connected to ESO’s ESPRESSO spectrograph, will provide high resolution disk-resolved and disk-integrated data, refining techniques for distinguishing stellar activity from planetary signals in RV measurements.