Larry,
It is very very unlikely. There was a transit of Mercury that Kepler tried
to observe. He realized after Galileo's sunspot observations that he had
seen visually a sunspot instead as it didn't move across the disk. If you
want I can check this further but I don't have the time right now.
Gary
Gary Karshner
St. Mary's University
San Antonio, Texas
KARSHNER@STMARYTX.EDU