Sample Essay on Galileo Galilei

Galileo Galilei


Born in 1564, Galileo Galilei was one of the most outstanding personalities in scientific revolution. His prominence was in his involvement in almost all areas of natural philosophy, which included astronomy, mathematics, and in what in the contemporary world of science is called physics (Willett, 2015). As one of the originators of modern scientific methodology, Galileo’s study of motions became the foundation of Isaac Newton’s principle of gravity and inertia. In addition, it also became the foundation of Aristotle’s laws on motion (James, 2004). The main objective of this essay will develop an in-depth perspective of Galileo Galilei’s life and his contribution to the world of astronomy.

Life story of Galileo Galilei

Born in Pisa, Tuscany in 1564, Galileo was the oldest of his six siblings. He came from a relatively normal family background and attended the University of Pisa after his father discouraged him from pursuing a career in priesthood. It was through his father’s convincing nature that Galileo was steered towards mathematics (Willett, 2015). During his initial studies in college, he was dedicated towards the acquisition of medical degree. However, after attending one of the geometry lectures, Galileo developed an interest and decided to pursue natural philosophy and mathematics instead of medicine (Willett, 2015). While studying at the University of Pisa, Galileo also developed an interest in fine art and his interest was demonstrated by his ability to teach courses on the techniques of perspectives at the Accademia delle Arti del Disegno in Florence, Italy.  The economic hardships that his family was facing in 1589 made it difficult for Galileo to complete his degree. However, in 1589 was offered a professorship and appointed the head of the mathematics department at the University of Pisa (Willett, 2015). This was following his writings on motions. At the end of 1592, Galileo moved to Padua where he was appointed a professor of astronomy and mathematics at the university. In 1609, Galileo used a newly built telescope to observe planets and confirmed the Copernican view that the solar system was composed of planets that revolved around the sun. His publications about his observations placed him in conflict with the Catholic Church and he was sentenced to life imprisonment, which he served under house arrest. Galileo dies in 1642 (Willett, 2015).

Galileo’s contribution to astronomy, science, and the impact of his work

In the course of his career, Galileo made different contributions in the world of science through his scientific discoveries in areas of astronomy, applied mathematics, and motion. Furthermore, Galileo also made several contributions to the field of applied science (Preston & Skamp, 2015). This was especially with regard to the improvements he made on the telescope, the invention of the thermoscope, and enhancements to the modern thermometer and improvements to the compass (Willett, 2015). His studies in motion led to an overthrow of the Aristotelian perspective of system motion. Through his perspective, Galileo opposed the a priori assumptions that defined the Aristotelian metaphysics. According to Aristotle, bodies had inherent properties, which impelled them to move to their natural resting places. Contrary to this assumption, Aristotle presented an argument on the empirical study of motion (James, 2004).

Galileo also inverted the earlier process of treating mathematics in connection with nature. Instead of trying to develop some form of reconciliation of nature with mathematics posited in advance, Galileo applied measurements and mathematics, and conducted experiments to his experimental observations (James, 2004). Through these initiatives, he began the process with observed motion bodies followed by deriving mathematical principles of motion on his observations.  Galileo’s approach to motions was considered as some form of development in the world of science considering its agreement with the modern scientific method. Through his works, he unveiled two essential principle of motion. The first principle is that of uniform acceleration which states that bodies, irrespective of their weight, often fall at the same rate and not at a rate proportional to their speed. The second principle is that of uniformity-accelerated motion. According to this principle, falling objects often increase in speed and uniformity depending on distance and time (Preston & Skamp, 2015).

An additional contribution to the world of science was the introduction of the notion of vectors to the study of projectiles. In this notion, Galileo argued that the movement of projectiles could be understood through the parabolic approach. The notion of vectors from the perspective of the parabolic motion of projectiles has been essenatil in military applications (James, 2004). This is because it has been used in the determination of the best angel that can be used in firing projectiles from guns to ensure the realization of an ultimate distance. From the notion of vectors, it was found to be when the gun barrel was positioned at angel 45 degrees of inclination from the horizon (Willett, 2015).

Through his improved version of the Lippershey’ telescope, Galileo had the ability to make additional astronomical discoveries which included the confirmation of planet Venus and the discovery of the four largest satellites that revolved around Jupiter (Preston & Skamp, 2015). The discovery of the four moons was important because it was a demonstration of a system where circular motion occurred around a center other than the earth. Galileo observed bulges around Saturn. In his initial observation, he described the bulges on Saturn as ears. This is because his telescope was less powerful to show him the bulges as a ring-surrounding planet Saturn (Preston & Skamp, 2015). This was a major contributor to the understanding of the structure of planets on the solar system. In addition, Galileo was also able to make observations, discoveries, and analysis of sunspots. This led him into publishing some of his findings in a book titled Sidereus Nincius in 1610 (Preston & Skamp, 2015).

After the publication of his findings, Galileo made additional discoveries on the phases of Venus, which led to the development of descriptions of the periodic phases resulting from the ability of Venus to orbit around the sun (James, 2004). The discovery made by Galileo was in agreement with the Copernican heliocentric model, which asserted that the solar system was composed of planets that revolved around the earth. Galileo’s analysis and observation of the sunspot were instrumental in the development of knowledge in the world of science because they were challenging the Aristotelian assumption that the sun was a flawless body (Willett, 2015).


Galileo Galilei made numerous discoveries in his lifetime and most of these can be associated with his ability to improve the existing telescope to enable an observation of the solar system. Galileo is credited as the first man to use the telescope to observe bodies beyond the earth. Galileo was the first to discover that the moon and the sun were not flawless bodies through the discovery and the observation of the sunspots.


James, I. M. (2004). Remarkable physicists: From Galileo to Yukawa. Cambridge [u.a.:

Cambridge Univ. Press.

Preston, C., &  Skamp, K. (2015). Teaching primary science constructively. South Melbourne:

Victoria Cengage Learning

Willett, J. (2015). Life of Galileo. London: Bloomsbury Publishing