I did a little bit more research on Galileo again, too. Just a refresher that helped a lot, because I had made up a comet that he spotted in 1603. That wouldn’t have happened. The telescope wasn’t invented until 1608, and he made improvements to the first in 1609. So 1603 became 1609 in my manuscript.
I am all about accuracy, even when I am making it up. It’s the little things that you pay attention to that really make a work of fiction believable.