Damasso, MarioMarioDamassoDEL SORDO, FABIOFABIODEL SORDOAnglada-Escudé, GuillemGuillemAnglada-EscudéGIACOBBE, PaoloPaoloGIACOBBESOZZETTI, AlessandroAlessandroSOZZETTIMorbidelli, AlessandroAlessandroMorbidelliPojmanski, GrzegorzGrzegorzPojmanskiBARBATO, DomenicoDomenicoBARBATOButler, R. PaulR. PaulButlerJones, Hugh R. A.Hugh R. A.JonesHambsch, Franz-JosefFranz-JosefHambschJenkins, James S.James S.JenkinsLópez-González, María JoséMaría JoséLópez-GonzálezMorales, NicolásNicolásMoralesPeña Rojas, Pablo A.Pablo A.Peña RojasRodríguez-López, CristinaCristinaRodríguez-LópezRodríguez, EloyEloyRodríguezAmado, Pedro J.Pedro J.AmadoAnglada, GuillemGuillemAngladaFeng, FaboFaboFengGómez, Jose F.Jose F.Gómez2025-03-102025-03-1020202375-2548http://hdl.handle.net/20.500.12386/36560By analyzing 17 years of radial velocity data of Proxima Cen collected with the UVES and HARPS spectrographs, we detected a signal of period P 5 years that could be explained by the presence of a second planet, Proxima c, with minimum mass m sin i 6. Earth masses. Together with the low-mass temperate planet Proxima b, this candidate planet would make Proxima the closest multi-planet system to the Sun. We will present the properties of the new RV signal and investigate the likelihood that it is related to a magnetic activity cycle of the star. We will discuss how the existence of Proxima c can be confirmed, and its true mass determined with high accuracy, by combining Gaia astrometry and radial velocities. Proxima c would be a prime target for follow-up and characterization measurements, especially with next generation direct imaging instrumentation due to the large maximum angular separation of ∼1 arcsecond from the parent star. Since the orbit would be beyond the original location of the snowline, Proxima c would challenge the models of the formation of super-Earths. Presently, this study is under review by Science Advances....ELETTRONICOenArticle10.1126/sciadv.aax74672-s2.0-85078690983https://www.science.org/doi/10.1126/sciadv.aax74672020SciA....6.7467DFIS/05 - ASTRONOMIA E ASTROFISICA