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This is CBSI in the world. I'm John Batchel with Govert Schilling, an astronomer chronicler, who is taking us into the part of astronomy that is the most confounding and tempting to astronomers, to cosmologists,

to people who read Govert's book.

We're looking for something that we can't see.

We've never found.

And we're going to try to imagine how we can certify it exists.

We need theory is wonderful. But how do we certify it? Now we come to

Jeremiah Osterker, who thanks to Govert, I've been led to his book, Heart of Darkness, published

just a few years ago. He is an astronomer with firm ideas, and one of those firm ideas

is to picture again what we can't see.

It's called the halo effect around our galaxy, the Milky Way, around all galaxies.

What is that? How should we picture it?

Yeah, it was a strange situation because, as we discussed before, Fritz Vicki was the one who really was the main one who realized there must be a lot of unseen matter in galaxies.

But no one paid too much attention back then.

...