I would find it difficult to believe that Nicolas Copernicus-(The Father of MODERN Astronomy, circa, the 1500's AD/CE), would NOT KNOW about his predecessors, in particular, his distant Ancient Greek Predecessors, such as Archimedes and especially, Aristarchus of Samos-(the earliest known Heliocentric Astronomer).
Copernicus lived a good part of his adult life in the Northern Italian Renaissance city of Bologna and trained to become a Catholic Priest. Yet, the city of Bologna, during Copernicus' time, was also, one of the more preeminent Renaissance Centers, as well as the location of its famed University of Bologna, which was one of the most prominent Schools of Higher Learning and Renaissance scholarship in the world. In this Academic environment, Copernicus-(despite his religiosity and Priestly ambitions), would have been well acquainted with the (Pre-Christian) ideas of Aristarchus and Archimedes.
The Ancient Greek Heliocentric model-(pioneered by Aristarchus and Archimedes), was essentially, Reintroduced to the Modern European West, via Nicholas Copernicus. However, Copernicus' Reintroduction of Heliocentricity to Europe was NOT a historical example of thievery, nor an early example copyright infringement/ violation. Rather, it was a more sophisticated, refined and comprehensive scientific explanation to a largely ignorant and skeptical Western public, as well as to a largely ignorant and skeptical Papal Bureaucracy-(which literally swore by the Geocentric model that was pioneered by Aristotle and reechoed by Ptolemy centuries later).
I also find it difficult to believe that a scientifically and mathematically oriented figure, such as Copernicus, would have been unaware of Medieval Islamic Mathematics and Astronomy. While Heliocentricity does not appear to have been central to Medieval Islamic Astronomy and Science, it is very likely that the intellectually vibrant atmosphere of Medieval Islamic cities, such as Toledo, Cordoba, Fes, Cairo and Baghdad, would have likely produced Thinkers, Commentators and Scholars, who may have seriously considered and discussed Heliocentricity, as a plausible scientific idea. An idea that, centuries later, would almost have certainly circulated throughout the Northern Italian Renaissance Cities, including, Copernicus' city of Bologna.
Overall, when examining the history of Heliocentricity, one can give Copernicus, the appropriate and deserving credit for his role in reintroducing and refining this ancient idea. However, Copernicus should also be appropriately and accurately positioned within a larger historical context in relation to his Islamic and particularly, his Ancient Greek predecessors and pioneers.