With respect to human inquiry, I don't know that you can really say who was the founding father of astronomy. People have been looking at the sky and wondering since before the invention of writing. However, if you want to know who was the founder of modern astronomy, the I would have to say that it was Nicolaus Copernicus. While he wasn't the first person to propose the Sun centered model of the universe, his proposal to that effect was the first to be taken seriously. So he is the man that started the revolution that took us from the general acceptance of the false idea that the Earth was the center of the universe to our current understanding of the universe. There were a number of other people who contributed to this understanding, but Copernicus was the person that got the ball rolling.