It may have sounded like a Bond villain's wildest dream only a few years ago, but diamond planets, i.e. planets made out of diamond, are a thing that exists. Not only that, they're not that uncommon either, scientists are pretty sure there's one several times the size of Earth in the neighborhood.
Granted, scientists may refer to these planets as carbon planets, but diamond is carbon and it's fair to say a "diamond planet" sounds a bit cooler than a "carbon planet."
Researchers at Yale University found one planet circling a nearby star, 55 Cancri, 40 light years away, basically in our own backyard.
55 Cancri e, the fifth planet discovered circling this star way back in 2004, is twice the size of Earth but eight times heavier, what's called a Super Earth, and there are indications that it could have conditions favorable to being a diamond planet.
The planet is very, very close to its star, a year only lasts 18 hours. It's distance to the star also accounts for the huge temperatures on the planet, 3,900 degrees Fahrenheit or 2150 Celsius.
The Yale team created a computer simulation, based on what's been observed about the planet, to try and determine what it's made of.
They believe the planet is mostly made up of carbon, at least the outer shell, which means there's graphite close to the surface and diamond further down because of the enormous pressure.
In fact, graphite along with diamond that was formed below and pushed up by volcanoes, makes up only a small outer shell.
Beyond that, the researchers believe that the layer of diamond could make up about a third of the radius of the planet. Further down, the diamond may actually be in liquid form. In total, a third of the weight of the planet may be diamond.
What's most interesting to scientists isn't necessarily what it's made of, but the fact that a planet that is similar in size to Earth can be so different. It was first thought that the planet would be similar to ours and that there may be large amounts of superheated water.
But that is not the case. While carbon is abundant on the planet, unlike on Earth where it's mostly on the surface, water and oxygen are very scarce.