Hubble

Did you know the universe is getting bigger every moment? Edwin Hubble was an American astronomer from the early 20th century (1889–1953).

His biggest discovery was that the universe is expanding: galaxies are moving away from us, and the farther they are, the faster they recede.

In the 1920s, using the giant Hooker telescope at Mount Wilson, Hubble measured the distances to other 'spiral nebulae' by finding Cepheid variable stars. That proved these fuzzy patches were entire galaxies far beyond our Milky Way. By combining distance measurements with observations of redshift — how starlight stretches when things move away — he found a simple rule now called Hubble's law.

Hubble also sorted galaxies into a simple 'tuning-fork' chart — spirals, barred spirals, and ellipticals — which helped astronomers understand galaxy shapes. His work changed our picture of the cosmos: it turned our tiny island of stars into one of billions of galaxies in an expanding universe and set the stage for the Big Bang idea. Today, the NASA Hubble Space Telescope carries his name and sends back gorgeous pictures that keep teaching us more. Edwin Hubble showed that the universe is bigger, busier, and more exciting than anyone had imagined — and that’s why we still celebrate him.