No, he isn’t a zombie.  He’s a long dead scientific pioneer. He discovered Saturn’s moon of Titan and was the first to suggest that Saturn’s odd ‘blob’ shape could be explained by rings around the planet.  He was a pioneer of optics and developed a telescope with two lenses, more powerful than Galileos. He also characterized the motion of an ideal mathematical pendulum (with a massless cord and a length longer than its swing), and invented the pendulum clock as a method of keeping time.  He had a few other contributions to astronomy, including the observation of individual stars in...