Galileo
Depending on whom you asked in 1609, Italian astronomer Galileo Galilei's procurement of a telescope was either the best thing to ever happen to astronomy or the biggest nuisance. By calling attention to astronomer Nicolaus Copernicus and his belief that Earth was a planet that orbited the Sun (not vice versa), Galileo began to incense both the Catholic Church and fellow scientists.
In 1632, with the permission of the Church — which had incorporated Aristotle's Earth-centric galaxy into its teachings — Galileo published Dialogue Concerning the Two Chief World Systems, supporting Copernicus's theory. He was condemned by the Holy Office of the Inquisition (a tribunal set up to eliminate heresy) and, at 69, sentenced to house arrest. Galileo went blind and died eight years later, just about 50 years before Isaac Newton's three laws of motion and principle of gravitation gave definitive proof to what Copernicus and Galileo had believed all along.