Which Polish astronomer published the heliocentric model in 'De Revolutionibus'?

Nicolaus Copernicus published the heliocentric model in De revolutionibus orbium coelestium, usually shortened to De revolutionibus.

Printed in 1543, the book argued that Earth is not stationary at the center of the cosmos. Instead, Earth rotates on its axis and travels around the Sun, while the other known planets also orbit the Sun. This challenged the Ptolemaic geocentric system that had dominated European astronomy for centuries.

Copernicus had developed the theory over many years and circulated an outline before publication. His pupil Georg Joachim Rheticus helped promote the work and persuaded him to publish it. An anonymous preface by Andreas Osiander presented the model as a mathematical hypothesis, partly to reduce controversy.

Copernicus still used circular orbits and epicycles, so his calculations were not dramatically more accurate than Ptolemy’s. The model’s lasting importance was conceptual: it helped launch the Copernican Revolution and influenced Galileo Galilei and Johannes Kepler. Tycho Brahe and Kepler later developed competing or improved planetary models.