A star, the size of the Earth, made out of...a diamond?! UWM astronomer has made a remarkable discovery!

MILWAUKEE (WITI) -- A University of Wisconsin-Milwaukee astronomer has made a remarkable discovery. Some say it's like "a diamond in the sky!" Dr. David Kaplan and his colleagues have discovered a dying star so old and so cold, it must be made out of a diamond!

Dr. Kaplan has the backing of NASA to continue his research on what basically constitutes "a diamond" in space -- the size of Earth!

In the Physics Department at UWM, one thing often leads to another. That's how Dr. Kaplan describes making the biggest discovery of his young career.

"It was sort of a thread -- we started teasing and started pulling and started pulling. This is the first time we know it's happening," Dr. Kaplan said.

More than a year ago, Dr. Kaplan joined a team of scientists studying a "pulsar" -- a very dense, highly magnetic dead star.

This pulsar was orbiting something else -- expected to be a white dwarf -- another kind of dead star.

"They're not uncommon, but usually not this interesting," Dr. Kaplan said.

But when they pointed their telescopes at it...it wasn't there!

"We saw nothing. We were basically led to this conclusion: There is an object there. This object is not a nutron star. It has to be a white dwarf. We don't see the white dwarf, and therefore, it must be really, really cold," Dr. Kaplan said.

So if this object is so cold, it led Dr. Kaplan to believe it is made up of something very flashy: a giant, Earth-sized diamond.

"We think that it's made up of 99.999 percent carbon and oxygen that has become so squeezed together -- sort of the way a diamond is formed in the Earth," Dr. Kaplan said.

Dr. Kaplan's findings have been published in the Astrophysical Journal. It has earned him some coveted one-on-one time with the Hubble Telescope.

This will be Dr. Kaplan's best chance at seeing this "diamond in the sky" for the first time.

"Then we can use those observations and tie them together with our models to figure out just what is going on," Dr. Kaplan said.

Dr. Kaplan certainly wasn't alone in this endeavor. Researchers from the United States and abroad have played roles in the eventual discovery of this diamond star.