He converted the idea of the "spyglass" into a telescope, discovered the Moon was not smooth and Jupiter had moons orbiting it.

Johann Kepler

Sir Isaac Newton

Galileo Galilei

Tycho Brahe

Galileo Galilei

Explanation:

Galileo first discovered that the Moon had mountains just like Earth. He also discovered 4 of Jupiter's moons. Using his telescope, Galileo made many observations of our Solar System. He came to believe that the idea that the Sun and other planets orbited around the Earth was not correct.