10 Great Inventions and Discoveries of Galileo Galilei.

Updated: Mar 9, 2021

Galileo Galilei was born on 15 Feb 1564 in Pisa, Italy. Galileo Galilei is one of the most recognizable astronomers of all time. His telescopic discoveries have contributed significantly to the field of Astronomy. He is regarded as the father of Modern Science, Modern Physics, Scientific Method, and Observational Astronomy. Here are ten great inventions and discoveries of Galileo Galilei.



1. He invented a thermoscope. It is a device that shows the variation in temperature. Thermometers are advanced, evolved version of a thermoscope.


2. He invented an instrument called Sector which helped in calculating problems in proportion, trigonometry, multiplication, and division till the 19th century.


3. Galileo discovered the principle that the density of a liquid varies with temperature. Galileo thermometers, named after him, works on this principle.


Telescopic Discoveries


When Galileo viewed the sky with his telescope. He made revolutionary discoveries that change the perspective of the universe that humans used to know.



4. He founded that the moon's surface isn't smooth. It has mountains, valleys, and craters.


5. The Sun has scar - dark spots - which is now acknowledged as Sunspot.


6. He noticed that the position of sunspots varies with time. After few observations, he concluded that the sun spins on its axis, about once per month.


7. Galileo was also the first person to discover moons of another planet. The four largest moons of Jupiter were seen by a person for the first time. These four moons are often called Galilean Moons.


8. The discovery of moons of Jupiter was in opposition to the Geocentric Model - which says that the Earth is the center and all the other bodies revolve around it. Clearly, This was not the case for newly discovered moons (at that time) of Jupiter.


9. Galileo also discovered that the planet Venus goes through phases, which can be interpreted only by its motion around the sun.


10. Galileo was not the first to build a telescope. The telescope was first applied for a patent in 1608. In 1609, Galileo made his own improved version of the telescope after learning about it.


In 1610, Galileo published his telescopic observations "Starry Messenger" which brought him in a dispute with the catholic church. He was asked to retract his claim about the Sun-Center idea, which he strongly denied. Galileo Galilei was then placed under house arrest for all his remaining life. During this period he wrote a book "Discourses and Mathematical Demonstrations Relating to Two New Sciences". Galileo became blind in 1638, the same year his book was published. He died at the age of 77 in 1642.