This is CBS Eye on the World.

Here's John Bachelor.

I welcome dark matter, what we know and what we want to know.

A new book, the Elephant in the Universe, 100 Years' Search for dark matter.

Guvert Shilling is the author and we begin 100 Years before this moment.

Jacobus Cornelius Coppitan, Coppton, born 1851 writes a paper in May of 1822 that is revelatory.

It's entitled First Attempt at a Theory of the Arrangement and Motion of the Ciderial System.

That paper has in it this sentence, the amount of dark matter from its gravitational effect.

Govert a very good evening to you. Thank you. Introduce us to Mr. Copton.

What was it that brought him to make that speculation that we now spend so much time puzzling over? Good evening to you.

Yeah, hello, very nice meeting. Thanks for having me.

Jacobus Copton was a Dutchist for the Merr and as you said, his paper in 1922 was a groundbreaking paper

because one century ago, astronomers hardly knew about the universe that we know of.

We now have this wonderful James Webb Space Telescope that is covering galaxies out to billions of light years away.

But 100 years ago, no one was even sure whether or not our Milky Way was alone.

And Copton was one of the few who thought that the Milky Way Galaxy was the only thing in the Universe.

It was later called the Copton Universe because he thought that was all there was to it.

And he thought that other spiral galaxies, spiral nebulae, as they called them,

were actually objects in the Milky Way. So he made this whole plan of his idea about the layout of our Milky Way system,

which to him was all of the Universe. And when he thought about that,

he realized that the gravity of all those individual stars had to be governing the stars' motions.

And then you can turn this idea on his head and say, if I study the motions of the stars,

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