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When I look into the night sky, I'm in awe of the stars I see lighting up our little

part of the universe.

But every time, I hope I'm lucky enough to catch some of them twinkly.

Which in itself is not rare because Starlight gets jumbled in our atmosphere, but that's

not the twinkling I'm searching for.

What I want is the rare twinkling that comes from the star itself.

I want to see the periodic brightening and dimming of the elusive variable star.

And in 1920, these unique stars became a distance measuring tool used to argue the great debate

between two astronomers.

Hollow, Shapley, and Herbert D. Curtis.

They debated our solar systems place in the cosmos, and if our larger Milky Way galaxy

was the entire universe.

When astronomer Dr. Vicki Scocroff says, that's what Harlow Shapley thought.

So Shapley did think that we were it, but he thought it was bigger than we could see,

but still not huge.

Whereas Curtis thought our own galaxy was a little bit smaller, but that there were also

other galaxies.

Those potential other galaxies they were debating were these fuzzy blobs or nebulae, like

the Magellanic clouds.

No one knew how far away they were or what they were, but Curtis' camp thought that some

of these blobs, these other galaxies, were other universes.

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