Shapley-Curtis Debate

The Shapley-Curtis Debate, held in 1920, was a pivotal discussion in astronomy about the nature of galaxies. Edwin Hubble, representing the Shapley perspective, argued that the Milky Way was the entire universe, with other nebulae being part of it. In contrast, Heber Curtis believed that these nebulae were separate galaxies, each potentially containing countless stars. The debate highlighted the need for better observational evidence in astronomy and ultimately paved the way for the understanding that the universe is vast, with many galaxies beyond our own, fundamentally changing our view of the cosmos.