Scientists Believe Super-Earth Planet 55 Cancri e May Be Covered With Diamonds

On August 30, 2004, astronomers discovered a planet 40 light years away orbiting a sun-like star.

The planet, named 55 Cancri e has half the mass of Neptune, almost 8 times more of the Earth. It is twice the width of the Earth classifying it as the first discovered Super-Earth.

Super Earth planets are more massive than the Earth but lighter than gas giants like Neptune. They can be made up of gas, rock or both. To date, there are around 70 discovered super-earth like planets with hundreds more waiting to be classified.

The planet, 55 Cancri e, orbits the star 55 Cancri A. It is the innermost planet in its planetary system, orbiting 55 Cancri A twenty-six times closer than that of Mercury to the Sun. It takes the planet eighteen hours for it to orbit the star.

Because of the proximity of 55 Cancri e to 55 Cancri A, temperatures of the planet when facing the star reaches more than 2,000 Kelvin or 3,140 Fahrenheit. This is hot enough to melt metal.

Several theories abound on the composition of the planet. An observation by the Spitzer Space Telescope suggests that 20% of the planet may be comprised of light elements and compounds, including water.

They believe that the water exists in both liquid and gas called a supercritical state. And that the whole planet is blanketed by steam. Since hydrogen has yet to be observed from the planet, it could be that instead of water, the compound could be made up of carbon dioxide.

Nearby super-Earth likely a diamond planet

New research led by Yale University scientists suggests that a rocky planet twice Earth's size orbiting a nearby star is a diamond planet.

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

A Planet Made of Diamonds

A new study suggests that some stars in the Milky Way may contain giant terrestrial planets that contain up to 50 percent diamond.

The diamond planet may be five times the size of Earth and weighs as much as Jupiter.

Wendy Panero, associate professor in the School of Earth Sciences at Ohio State, and doctoral student Cayman Unterborn constructed computer models of the minerals that form in planets composed with more carbon than Earth. These "carbon super-Earths" may not be able to sustain life though.

A carbon super-Earth's interior would quickly freeze since diamonds transfer heat readily. This would mean that the planet has no geothermal energy, no plate tectonics, and no magnetic field or atmosphere.

"We think a diamond planet must be a very cold, dark place," Panero said.

On a related note, astronomers in Australia have reported discovering a Diamond Planet orbiting a pulsar. Watch the two videos.

Geologist have verified what they long have suspected; that the a layer of diamonds likely exists in the Earth's lower mantle, just above the core.

Video: News Report on the Diamond Planet

Based on the result, a further model was constructed to see what would happen to the composition of a carbon super-Earth with the same conditions. What they found was that the planet could become very large, with iron and carbon merged to form a kind of carbon steel in the core, and vast quantities of pure carbon in the mantle in the form of diamond.

The researchers discussed the implications for planetary science.

"To date, more than five hundred planets have been discovered outside of our solar system, yet we know very little about their internal compositions," said Unterborn, who is an astronomer by training.

"We're looking at how volatile elements like hydrogen and carbon interact inside the Earth, because when they bond with oxygen, you get atmospheres, you get oceans – you get life," Panero said. "The ultimate goal is to compile a suite of conditions that are necessary for an ocean to form on a planet."

Video: Astronomer Report on the discovery of the Diamond Planet