 The work at Frombork’s museum and the person of the great Polish Astronomer Nicolas Copernicus, who spent most of his life in Frombork and Warmia region, made a lasting impression on Sikorski.As a result, Copernicus and "Copernicana" research became the dominant subject in Sikorski's lifetime work and in his professional affiliations with various research centers.Ultimately, it led to Sikorski's discovery and publication of Copernicus' resting place at Frombork’s cathedral in 1973, which was confirmed archaeologically in 2005.