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Very Fancy: Scientists Detail A Diamond Encrusted Super-Earth

Illustration of the interior of 55 Cancri e — an extremely hot planet with a surface of mostly graphite surrounding a thick layer of diamond, below which is a layer of silicon-based minerals and a molten iron core at the center.

hide captionIllustration of the interior of 55 Cancri e — an extremely hot planet with a surface of mostly graphite surrounding a thick layer of diamond, below which is a layer of silicon-based minerals and a molten iron core at the center.

Haven Giguere/via Yale University

Scientists have discovered a world much fancier than our homely, little Earth.

New research that will published in the journal Astrophysical Journal Letters details a planet that is eight times heavier than Earth and with twice its radius. But instead of being covered in water and granite, it is encrusted in graphite and diamond.

"This is our first glimpse of a rocky world with a fundamentally different chemistry from Earth," lead researcher Nikku Madhusudhan, a Yale postdoctoral researcher in physics and astronomy, said in a statement.

That's why this is scientifically important. But, in truth, we're distracted by shiny things. So we wonder: How did these scientists know that 55 Cancri e, the technical name of the planet, which is 40 light years away, is so fancy?

The New Scientist says that at first the scientists believed that it was covered in "supercritical water," or water that walks the line between gas and liquid.

The New Scientist adds:

"[Olivier] Mousis and colleagues reckon this assumption is unsupported because the planet's star, 55 Cancri, is richer in carbon than it is oxygen. Recalculating with that in mind, taking the planet's mass and radius into account, suggests that about a third of that mass is carbon.

"Based on estimates of the temperature and pressure throughout the planet, this carbon could be in the form of diamond, which requires extreme conditions to form. One of five known planets in its solar system, 55 Cancri e, sits very close to its host star. 'When you form diamond, it's only a matter of temperature and pressure, and the temperature is very high on the surface,' says Mousis."

The diamond planet, by the way, also moves much faster than our own. Its year lasts just 18 hours and its temperature hovers around the 3,900 degree Fahrenheit mark.

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