Star Astronomy

Galileo Galilei was born in 1564 near Pisa in Italy where he became a prominent scientist, astronomer and mathematician. Using his mathematical knowledge he designed and constructed a Galileo telescope using a combination of refracting lens which was far more powerful than the more common spy-glasses being used by other astronomers. He used his telescope to study lunar craters and mountains, sunspots, the phases of the planet Venus as well as discovering four moons revolving around the planet Jupiter which are known as the Galilean moons after him.

His works and theories are considered to be some of the most influential of the time, with many of his mathematical concepts still in use today and taught in schools and educational establishments throughout the world include experiments from which he determined the theory of the speed of falling objects, mechanics and pendulums.

Galileo’s mathematical descriptions ‘the Laws of Inertia’ was used by Isaac Newton as the basis for his ‘First law of Motion’.

His works included using his new telescope to convince him of the Copernican theory, that the sun was the centre of the universe and that the earth and all of the other planets revolved around the sun not the earth, which was proposed to him by Nichols Copernicus. This work was very controversial at the time as people believed that the earth was the centre of the universe and led to him being accused of heresy by the Catholic Church, as such he was forbidden from teaching or discussing his theories.

Galileo Galilei also renowned for his applied science and technology including improving the design of the geometric and military compass which was used by gunners to elevate guns more safely and surveyors used the compass to construct regular polygons.

Another invention for which Galileo is famous for designing is the Galilean thermometer (named after him) which is also known as a thermoscope.

Galileo’s book ‘Dialogue Concerning the Two Chief World Systems’ discussed the arguments for and against the Copernican theory and he was again accused of heresy. Galileo was sentenced to life imprisonment after appearing before the Inquisition in Rome. This conviction was later reduced and he spent the rest of his life under house arrest at his villa near Florence. Galileo was made to publicly withdraw his support for the Copernican theory.

In 1638 Galileo Galilei wrote another book, ‘Discourses Concerning Two New Sciences’ it contained his ideas on the laws of motion and the principles of mechanics. Arguably his most widely used invention is the Galileo telescope, which is the basis for most moderation telescopes today.