This is John Baxter, conversation with my colleague, Dr. Ken Croswell, an astronomer, about a discovery that is fresh and unique so far.

A solitary black hole without a companion star.

Black holes are conceived as the result of a massive star collapsing, and then it has a companion, a binary companion, that revolves around it, and that's how we discover the black hole.

We can see something going around, something we can't see.

Well, this is the discovery of a black hole that doesn't have a companion, a solitary black hole. Ken describes it in great detail how they

found it and how they tested it and the joy of discovery. Dr. Ken Croswell, a black hole all by itself, no companion, towards the galactic center,

5,000 light years from Earth.

More of this tonight.

Good evening, John.

A black hole is a massive star that has collapsed and died and is so dense that its gravity doesn't allow anything to leave it, not even light the fastest thing in the universe. So these are very extreme objects, and one reason we like to study them is because

they are so extreme. So they test the laws of physics at the limit. And also, this is one of the

fates of stars, some stars, very few stars. Most stars do not become black holes. Most stars become something else when

they die. But these black holes are of great interest. And also in the explosion of material

that may precede the birth of the black hole, there can be new elements, new chemical elements

generated, such as things like gold and platinum.

And so these objects help us learn more about the chemical evolution of the Milky Way galaxy.

One particular black hole is of interest in Ken's article. I read the title from Astrophysical Journal.

An isolated stellar mass black hole confirmed using new Hubble Space Telescope astrometry

and updated photometry.

All right.

Isolated stellar mass.

That's significant to this paper.

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