In early 1610, who discovered with his newly invented telescope that Jupiter has four moons?

Galileo Galilei

The correct answer is option 3. Galileo Galilei.

In early 1610, the person who discovered with his newly invented telescope that Jupiter has four moons was Galileo Galilei.

Galileo Galilei, an Italian astronomer, physicist, and engineer, made numerous groundbreaking discoveries using his newly invented telescope. Among these discoveries was the observation of four large moons orbiting Jupiter. These moons are now known as the Galilean moons in honor of Galileo's discovery. They are named Io, Europa, Ganymede, and Callisto. Galileo's discovery provided evidence for the heliocentric model of the solar system proposed by Copernicus, as it showed that not all celestial bodies orbit the Earth.