A telescope.
Galileo Galilei first used a telescope to look at the stars in 1609.
Galileo Galilei first used the "new" telescope in 1609
Galileo in 1609
in 1609 Galileo made first telescopes
Yes they where by Galileo in 1609.
By 1609 Galileo had a telescope that magnified 20x
The telescope was invented by Hans Lippershey, a spectacle maker from the Netherlands, in 1608. However, another spectacle maker and astronomer, Galileo Galilei, was the first to use the telescope for astronomical purposes in 1609.
In this sentence, "In 1609" and "Galileo" would be classified as a time period and a proper noun, respectively.
Galileo
The telescope was first used by the Italian astronomer Galileo Galilei in 1609. Galileo made significant observations of celestial bodies such as the moon, Jupiter, and Venus using his telescope, which played a crucial role in revolutionizing our understanding of the universe.
Telescopes, were essentially discovered in 1609. Galileo and later Keppler were the first astronomers to use them. They caught on rapidly as observing instruments and for look out purposes., it took the optician's a while to correct the inverted view on some of them, but once done, they took off.
The Italian astronomer Galileo Galilei was the first to observe that the moon had craters. He made this discovery in 1609 through his telescope.