Planet Full of Diamonds Just 40 Light Years Away

Diamonds are considered to be women's best friend and they are found in abundance in a newly discovered planet '55 Cancri e'. At least a third of Cancri e, equivalent of about three times the Earth mass, is said to be made of diamonds. Twice the size of Earth, the planet is in Constellation of Cancer at a distance of 40 light years and visible to naked eye. 

"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."

It is one of five planets orbiting a sun-like star at a speed that makes a year on '55 Cancri e'  last just 18 hours unlike Earth's 365 days. It is incredibly hot at 3,900 degrees Fahrenheit rendering it non habitable.

The existence of this planet came to light when it was transiting its star last year. It was then the astronomers were able to measure its radius for the first time. Based on the new information and the most recent estimate of the mass, Madhusudhan and colleagues could infer its chemical composition using models of its interior and computing all possible combinations of elements and compounds that would yield those specific characteristics.

It was reported earlier that the host star has more carbon than oxygen. Madhusudhan and colleagues confirmed that during the planet's formation considerable amounts of carbon and silicon carbide, and a negligible amount of water ice was available.

According to Madhusudhan, astronomers thought that 55 Cancri e contained a substantial amount of super-heated water, based on the assumption that its chemical makeup was similar to Earth's. But the new study does not show any evidence of water in the newly discovered planet. It is composed primarily of carbon (as graphite and diamond), iron, silicon carbide, and, possibly, some silicates. 

"By contrast, Earth's interior is rich in oxygen, but extremely poor in carbon -- less than a part in thousand by mass," says co-author and Yale geophysicist Kanani Lee.

"The identification of a carbon-rich super-Earth means that distant rocky planets can no longer be assumed to have chemical constituents, interiors, atmospheres, or biologies similar to those of Earth," Madhusudhan said.

The discovery also opens new avenues for the study of geochemistry and geophysical processes in Earth-sized alien planets.

"Stars are simple -- given a star's mass and age, you know its basic structure and history," said David Spergel, professor of astronomy and chair of astrophysical sciences at Princeton University, who is not a co-author of the study. "Planets are much more complex. This 'diamond-rich super-Earth' is likely just one example of the rich sets of discoveries that await us as we begin to explore planets around nearby stars."

The details of this finding have been accepted for the publication in the journal Astrophysical Journal Letters.