In this episode of Our Island Universe, everything is moving.
Transcript:
Nine years after the “Great Debate” Edwin Hubble discovered that not only are there other galaxies, but they’re also moving away from us! In fact, the further away a galaxy, the faster it is moving away from us! In less than 10 years, we went from the idea that the Milky Way was all there is, too the idea that there are many more galaxies and that they’re speeding away from us! The Expanding Universe was born!
But wait! If the Universe is now expanding, doesn’t that imply that it was smaller in the past? And that if keep going further back, that the entire Universe would have been a single point? This point, later called the Big Bang, was the beginning of the Universe as we understand it today.
In fact, our Universe is weirder still! Not only are galaxies moving away from us, the rate at which they’re moving is changing! The Universe is not only expanding, it is accelerating! And we have no idea why. And this energy, this stuff, that’s causing the acceleration — this ‘dark energy’ — makes up 96% of the Universe and we have no idea what it is. To me, it’s not that we don’t know what it is or why its there — that’s science — its more that we have uncovered these clues that tell us our Universe is much more exciting than we’ve imagined! And is our Universe the only Universe?
Maybe.
Maybe not.