Final answer:
Galileo Galilei was the first scientist to use telescopes to observe planets and stars, leading to significant discoveries.
Explanation:
Galileo Galilei was the scientist who used one of the first telescopes to observe planets and stars. In 1610, he made groundbreaking discoveries through the telescope, such as observing the moons of Jupiter and the craters on the Moon. Galileo's use of the telescope revolutionized our understanding of the universe.
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https://brainly.com/question/517205
