Nicolaus Copernicus was a Renaissance polymath, active as a mathematician, astronomer, and Catholic canon.
Andreas Osiander was a German Lutheran theologian and astronomer who introduced Nicolaus Copernicus' heliocentric model to a wider audience.
Georg Joachim Rheticus was a German mathematician and astronomer who collaborated with Copernicus and popularized the heliocentric model of the universe.
Christopher Clavius was a German Jesuit mathematician and astronomer who helped develop the Gregorian calendar and mapped the stars with precision.
Michael Maestlin was a German astronomer and mathematician who played a significant role in the acceptance of the heliocentric model of the solar system.