In the 1920s, Edwin Hubble was observing the stars and noticed something pretty cool - the redshift of light coming from distant galaxies. This meant that those galaxies were moving away from us, and the farther away they were, the faster they were moving. It was like the universe was one big, never-ending game of cosmic tag!
Hubble's discovery was a total game-changer in the world of astronomy. It helped us understand that the universe is still growing and evolving, and that it's been doing so for billions of years. The expansion of the universe is still happening today, and it's getting faster and faster all the time - talk about a cosmic rush!
