Answer:
Galileo is known as one of the greatest astronomer and a scientist whose inventions led to the new discoveries in the solar system.
His great contribution to the scientific tool was the improvement of the low power telescopes to observe the solar system. With the help of his telescope, he examined the system and observed the craters and mountains of the Moon, discovery of the moons of the Jupiter and the descriptions of the sunspots.
These discoveries supported the heliocentric model of the Copernicus which helped the spread of his ideas to the world.