NASA and Carnegie Science are celebrating the centennial of Edwin Hubble’s landmark discovery that opened the universe to the vastness it contains. A century ago, using the Hooker Telescope at Mount Wilson Observatory, Hubble identified a Cepheid variable star, V1, which was nestled in the Andromeda galaxy. This pivotal finding shattered the long-held belief that the Milky Way was the entire universe, revealing many galaxies beyond our own.
Hubble’s observation in 1923 was what marked the rise of modern cosmology. Using the distance that he measured from V1, Hubble showed Andromeda is far beyond the Milky Way expanding human beings’ perception of the size of the universe. His observation of the redshift phenomenon in light that comes from remote galaxies further confirmed the expansion of the universe, thereby giving birth to Hubble-Lemaître’s Law.
The ripples of Hubble’s work ran deep. He set the stage for the Big Bang theory and an ever-expanding universe. Although Hubble himself was not too convinced of some of these interpretations, the work he undertook was vindicated by further development, with even the highly accurate measurements of the Hubble Space Telescope, operating continuously for more than 30 years.
The Hubble Space Telescope, honoring Edwin Hubble, has gone on to expand this legacy by observing cosmic phenomena such as crashing galaxies, supernovae, and the puzzling acceleration of the universe brought about by dark energy. Such contributions have helped fine-tune the current estimate of the age of the universe to some 13.8 billion years.
The celebration of this centennial by NASA coincides with the 245th meeting of the American Astronomical Society in Washington, D.C., marking the long-term influence of Hubble on science. Today, the questions he has opened continue to be pursued, including dark energy and the expansion of space itself. New missions, such as NASA’s Roman Space Telescope, promise further unraveling of the universe’s mysteries.
Edwin Hubble’s observation changed the way humans look at where they belong in this universe. His discovery not only multiplied our knowledge of the universe but also inspired many generations of scientists and space enthusiasts to explore the unknown. Today, NASA, along with the international scientific community, stand as witnesses to this hundredth year of discovery initiated with that faint smudge of light in the Andromeda galaxy.
