If I recall, Sheldon claimed that যীশু was born in the summer. I've heard that he was born at several different times, depending on the source-- some say he was born in the spring, others say autumn.
According to
link, which uses Biblical clues, "the most probable time for His birth occurred between September 16 and 29."
Tragically, Sheldon was wrong about Newton, who (as verified দ্বারা
link), was born on January 4th, 1643.
Keep in mind that it wasn't Sheldon, necessarily, who was wrong-- it was the writers of the show.