Question

Who used a telescope first and discovered phases of Venus, mountains on the moon, sunspots, moons of Jupiter, and that the Milky Way is made of stars?

a) Galileo Galilei
b) Johannes Kepler
c) Tycho Brahe
d) Nicolaus Copernicus

Answer 1

Galileo Galilei was the first to use a telescope to make significant astronomical discoveries, including the phases of Venus, mountains on the moon, sunspots, moons of Jupiter, and the true nature of the Milky Way.

Step-by-step explanation:

The individual who first used a telescope and discovered the phases of Venus, mountains on the moon, sunspots, moons of Jupiter, and that the Milky Way is made of stars was Galileo Galilei. While telescopes were not invented by Galileo, he improved upon their design and was the first to use them for significant astronomical observations. His work provided evidence supporting the Copernican model and changed our understanding of the cosmos.

Galileo's observations of Venus’ phases were instrumental in disproving the Ptolemaic model of the solar system. He observed moons orbiting Jupiter which was the first discovery of objects orbiting a body other than Earth, identified features like craters and mountains on the moon's surface, and noticed that the seemingly white band across the night sky, the Milky Way, was actually comprised of countless individual stars. These monumental discoveries with his early telescopes revolutionized the field of astronomy.