Williams Bay, Wisconsin USA - July 3rd, 2023: Yerkes Observatory owned by The University of Chicago holds the world's largest refracting telescope once used by U.S. Government and NASA. Poster #705577724
Williams Bay, Wisconsin USA - July 3rd, 2023: Yerkes Observatory owned by The University of Chicago holds the world's largest refracting telescope once used by U.S. Government and NASA. Poster #705577724
