Question: Hey, how do you think the theory of Redshift and the Doppler Effect has increased our understanding of the universe?

Jenn Wadsworth answered on 17 Mar 2016:

It’s completely changed the way we look at the universe! Before we measured the redshift of the galaxies, people thought the universe was static and unchanging. But the redshift indicated it was actually expanding, which meant there was a beginning (big bang). Since then we’ve found out that not only is the universe expanding, but also accelerating!