July 27, 2007

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Gas Giants Make Graphite But Stars Make Diamonds

Gas Giant planets probably have atmosphere full of pencil lead. But white dwarf stars may be diamond factories. Karen Hopkin reports.

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July 27, 2007  Gas Giants Make Graphite But Stars Make Diamonds

This just in: diamonds are not likely to form in the atmosphere of gas giants…planets such as Uranus and Neptune.

Now, if I know you, you probably *never* thought to look for diamonds in the outer reaches of our solar system. But that’s what physicists were recently contemplating. In the carbon-rich atmospheres of these giant planets, they figured diamonds might just rain from the sky. Or at least crystallize there.

But in an upcoming issue of the journal Physical Review Letters, physicists from Amsterdam in the Netherlands say: no way. According to their calculations, the temperatures and pressures present in and around planets like Uranus would be more suitable for generating graphite. Yes, the atmosphere around our outermost planets could be filled with pencil lead.

But wait…there’s more. The same scientists contend that white dwarves…which are the end-stage of the great majority of stars in our galaxy…are veritable diamond factories. Conditions there are perfectly suitable for transforming carbon atoms into sparkling gems. Indeed, three years ago astronomers spotted a white dwarf whose core appeared to be a diamond 2500 miles wide.  Now that would make an engagement ring that would break your finger, and your bank account.

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Gas Giants Make Graphite But Stars Make Diamonds