Christiaan Huygens, a Dutch philosopher and mathematician, was one of the leading scientists in the 17h century. He started by trying to disprove theories that had been established by Ancient Greeks in geometry. He was interested in telescopes and astronomy, anc spent a lot of time designing methods to improve the mechanical and optic performance of telescopes. In his book entitled "Systema Saturnium' published in 1659, he noted the discovery of the rings around the planet Saturn, and made observations about the planets, the Moon, and Orion Nebula. His keen interest in the field of astronomy led him to measure time and other matters that relate to mechanical physics. One of his most important contributions was that he explained the vital principles of classical physics like centripetal force and gravity in a vacuum in another book of his. Huygens also put forward a theory explaining the wave behaviour of light. His reputation as a scientist and a scholar became known worldwide, and remains so to this day.
Nicholas Copernicus was 15 century astronomer and mathematician, translator artist and physicist among other things He is best known as the first astronomer to put forward the idea of a system in which the planets and planetary objects orbit the Sun. By 1508, Copernicus had begun to create his model of the planetary system, suggesting that the Sun, and not our Earth, was the centre of the Universe. His model of the Universe was accepted, whereas earlier models had not been, because his was more detailed and accurate. He also had a better formula for the calculation of the positions of the planets at different times of the year. The Roman Catholic Church criticised Copernicus' theories. It went so far as to ban his book 'De Revolutionibus Orbium Coelestium,' after he died, and it remained a forbidden book for almost three hundred years. The ideas of Copernicus were instrumental in the evolution of the field of astronomy. In fact, almost every notable astronomer who came afte...