Who discovered Jupiter?
We can't say who first discovered the planet Jupiter because people have pretty much always known about it.
Jupiter is a bright, very obvious object in the night sky. As such, people have known about Jupiter since prehistoric times. As well as being one of the brightest things in the sky, it moves differently to the background stars in a similar way to the other planets in our Solar System. For anyone looking at the night sky for any period of time, you can't really miss Jupiter.
Although ancient people knew about Jupiter and gave it various names, they didn't know what it was. It wasn't until the invention of the telescope that people were able to see that Jupiter is a giant planet.
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