Copernicus is the father of our modern astronomy. He went against the opinion of the church by supporting a heliocentric view of the universe. In fear of being punished, though, he decided against publishing his findings until he was already old, and had less fear of being locked up for life.
The accepted view of the universe at this point was thought up by Aristotle and supported by Ptolemy, another predominant scientist. The church also supported their geocentric view, as it followed their religious beliefs. The scientists believed that, because the Earth didn't look like it was moving, it couldn't have been; science is based off of observation.