Which telescope was first used to observe the skies?
Galileo's telescope
Hubble Space Telescope
Gran Telescopio Canarias
Leviathan of Parsonstown

Galileo's Telescope

Explanation:

The science of astronomy took a huge leap forward in the first decade of the 1600s with the invention of the optical telescope and its use to study the night sky. Galileo Galilei did not invent the telescope but was the first to use it systematically to observe celestial objects and record his discoveries