Explanation

Galileo di Vincenzo Bonaiuti de' Galilei was an Italian astronomer, physicist and engineer, sometimes described as a polymath. 

Galileo was the first to point out the obvious: all motion is relative.

Galileo Galilei is famous for:

 he was the first to report telescopic observations of the mountains on the moon,

the moons of Jupiter, the phases of Venus,

and the rings of Saturn

He invented an early microscope and a predecessor to the thermometer.

ND11-07-2023