While both Copernicus and Tycho contributed to the evolution of astronomy and the Scientific Revolution in general, the nature of their accomplishments and challenges to the status quo were fundamentally different and defined their respective receptions by the scientific community at large. Copernicus essentially chose the wrong concepts of the commonly accepted cosmology (Ptolemaic model) to challenge. He obviously departed from Aristotelian cosmology with the concept of a heliocentric system, and this system was too anti-Aristotelian (and consequently, anti-religious) to be widely adopted. Moreover, his writing ability was lackluster, and De Revolutionibus was read by only a few astronomers. Of course, Copernicus was also unable to prove his system superior to Aristotle’s. He did not theorize new laws of physics to explain how or why the planets revolved around the sun; scientists therefore remained skeptical as to the viability of his system. However, Tycho challenged a less fundamental aspect of the cosmology, the concept of physical celestial spheres. As an Aristotelian concept, it was still firmly embedded in the minds of astronomers and natural physicists, but it was not as controversial as Copernicus’s assertion, which removed the special nature of the Earth. Tycho also relied on solid observational data to corroborate his claims, while Copernicus left his system largely unsupported, as previously mentioned. Due to this solid support, Tycho’s removal of the celestial sphere from his cosmology became widely accepted. In fact, when the pure Ptolemaic planetary model was refuted by Galileo’s observations with his telescope, geo-heliocentric models became much more popular, and Tycho’s model became one of the most commonly used. Thus Tycho actually furthered the evolution of astronomy much more immediately than Copernicus, as his ideas were accepted and supported with data. Of course, Copernicus still retains the credit for beginning the Scientific Revolution, as he was the first to seriously challenge the Aristotelian cosmology and Ptolemaic model.