Nearby Super-Earth is Likely a Diamond Planet Say Yale Scientists

Posted on October 11, 2012

Yale University researchers say they have discovered that a super-Earth planet orbiting a nearby star is likely a diamond planet. A thick layer of diamond is thought to exist underneath the planet's mostly graphite surface. The planet, 55 Cancri e, has a radius twice that of Earth and a mass eight times greater. The planet orbits a star located 40 light years away in the constellation of Cancer. There are also four other planets known to orbit this particular star.

55 Cancri e rotates around its star in just 18 hours. The temperature on the planet is about 3,900 degrees Fahrenheit. The researchers say the planet is void of water. They say it is "composed primarily of carbon (as graphite and diamond), iron, silicon carbide, and, possibly, some silicates."

Nikku Madhusudhan, a Yale postdoctoral researcher in physics and astronomy and lead researcher of the study, said in a release, "This is our first glimpse of a rocky world with a fundamentally different chemistry from Earth. The surface of this planet is likely covered in graphite and diamond rather than water and granite."

A paper about the diamond planet, "A Possible Carbon-rich Interior in Super-Earth 55 Cancri e," has been accepted for publication in the journal Astrophysical Journal Letters.

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