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Space ScopeA century ago, our understanding of the universe was dramatically smaller.In 1922, astronomers were still debating whether the mysterious “spiral nebulae” were objects inside the Milky Way or distant galaxies of their own. At the time, the known cosmos was essentially thought to be the scale of the Milky Way—about 100,000 light-years across.Today, we know the Milky Way is just one galaxy among hundreds of billions in the observable universe, which spans roughly 93 billion light-years across.In just over a century, our cosmic perspective expanded from one galaxy to an observable universe filled with an enormous cosmic web of galaxies.And perhaps the most mind-blowing part? The observable universe may be only a fraction of the entire universe, with regions beyond our cosmic horizon potentially extending far beyond what we can ever observe. Source: NASA, ESA, and modern observational cosmology.#Universe #Astronomy #Cosmology #Galaxies #Space