Speaking of the ringed planet Neptune
Did Galileo Discover Neptune? Galileo's Notebooks May Reveal Secrets of New Planet
http://www.spaceref.com/news/viewpr.html?pid=28689
"Galileo knew he had discovered a new planet in 1613, 234 years before its official discovery date, according to a new theory by a University of Melbourne physicist."
Though I distincly recall it from a book published in 1988 on the outer planets.
