Galileo
The Italian scientist Galileo Galilei (1564-1642) was a physicist, mechanic, and astronomer. After conducting many experiments, he studied the laws of falling bodies and their movement at an angle to the horizon, determined the dependence of the period of oscillation of the pendulum on its length, put forward the idea of the relativity of motion.
In 1609, Galileo designed a spotting scope with two glass lenses - a plano-convex objective and a plano-concave eyepiece. The tube gave a direct imaginary image of the object with a magnification of three times. Then he built a second tube with a magnification of 32 times and used this instrument to observe the sky. The scientist for the first time saw something that was not previously available to the human eye: what
there are mountains and plains on the Moon, that Jupiter has four satellites, that the Milky Way consists of a huge number of stars, that Venus changes phases like the Moon (this can only happen when it moves around the Sun), that there are spots on the Sun.
Thus, Galileo confirmed the correctness of the teachings of Copernicus. He described his discoveries in the book "Star Messenger". In 1633, Galileo was tried by the Inquisition and sentenced to life imprisonment. He was promised a mitigation of punishment in the event of a public renunciation of the "Copernican heresy." The aged scientist signed the renunciation, remaining internally convinced of his scientific correctness.
Credit - Big encyclopedia of astronomy
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