Editor says, what if Galileo had paid more attention to the planet Neptune, the "dim star" he noticed in 1612? Muses Jeff Provine on the This Day in Alternate History web site. Please note that the opinions expressed in this post do not necessarily reflect the views of the author(s).
Editor says, in reality Galileo would note the "dim star" but not notice it sufficiently. He would be notoriously bigoted about his scientific opinions, scoffing at Kepler and Grassi, even though they were correct about tides and comets, respectively. His opinions clashed with those of the Church, and Galileo would be forced to recant heliocentrism and spend the rest of his life under house arrest. Uranus would be mistaken by John Flamsteed as a star and not determined as a planet until William Herschel in 1781. Neptune, though observed by Galileo, would not be discovered until 1846 by Johann Galle. Editorial comments are entered in [light green] typeface.