Expansion of the Universe Explained | Cosmology 101 Episode 1

In this episode of Cosmology 101, we dive into the concept of an expanding universe. From the first moments of the Big Bang, our cosmos has been stretching in every direction. We explore what this expansion means for us, how we know it's happening, and the fascinating implications of living in an ever-growing universe.

Join Katie Mack, Perimeter Institute’s Hawking Chair in Cosmology and Science Communication, on an incredible journey through the cosmos in our new series, Cosmology 101.

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Milky Way image: NASA/JPL Caltech

[Moewenfels]

Every time i try to think about whats BEYOND our universe i kinda lose my thought.
As if i cant even imagine it.

[fabiocaetanofigueiredo]

We don't live in the universe. We ARE the universe (parts of it, but a part of something is still that something).

[iggyzorro]

'getting less dense' - very clever

[nagzi]

That last point was a banger. I'm going to have to use sometime myself.

[precbsfender]

"A trillion galaxies in our universe"..damn that's HUGE..

[Moewenfels]

So that slinky is kind of terrifying.
If the universe expanded in a big bang, could this be some kind of cycle?
Where the universe will collapse at some point and have another big bang happen?

[adams]

I am ever so slightly less dense now, thanks!