A recent study conducted by a team of investigators from Yale University in the US and from the Institut de Recherche en Astrophysique et Planetologie in France suggests the existence of a planet in the Milky Way made mostly out of carbon.
The planet, known as 55 Cancri e, has twice the Earth’s size and eight times its mass. It is located 40 light years away from Earth in the constellation of Cancer. It is one of the five planets orbiting the star 55 Cancri, which is visible to the naked eye from our planet.
The planet has a hyperspeed orbit, only 18 hours, and a temperature of 2,150 degrees Celsius (13,900 degrees Fahrenheit).
The scientists conducting the investigation believe the planet has a unique constitution, very different from the Earth’s. They believe the planet is made mostly by iron, silicon carbide, carbon, and other silicates. They estimate that with such an amount of carbon in the planet, at least one-third of its mass could be diamond (one of the forms of stable carbon)
This discovery may change the way astrophysicists understand planetary systems and their evolution. According to the lead author of the research, Nikku Madhusudhan, “This is the first glimpse of a rocky world with a fundamentally different chemistry from Earth’s,” and this means that the distant rocky planets can no longer be assumed to have chemical constituents and atmospheres similar to Earth’s. A carbon-rich composition could also influence the planet’s thermal evolution and plate tectonics with several implications to its eventual life forms.
The study has been accepted for publication in the Astrophysical Journal Letters.