Mercury is the smallest planet in the Solar System, but that doesn’t mean it can’t be hiding a secret that no one would have thought possible. NASA has just discovered it and scientists have been left perplexed by a discovery that, in recent times, has left everyone very surprised. Now new opportunities are opening up to continue investigating this planet that could still hold more secrets.
Mercury has long been a mystery to astronomers. The planet has more layers than one might think and raises many doubts and questions that specialists hope to be able to answer one day. Its dense core or the fact that the planet’s volcanic era ended much earlier than usual are factors that have always attracted attention. Now, the mystery surrounding Mercury grows even more due to this discovery.
A layer of diamond
Thanks to information provided by NASA’s Messenger mission, scientists have discovered that there is something even stranger than the planet’s dark surface: the presence of a thick layer of diamond, more than 16 km thick, beneath the planet’s crust.
Until now, we already knew that Mercury had a covering that had possibly been formed as a result of the existence, in the past, of a magma ocean. This ocean would have given Mercury some of its best-known characteristics, such as the graphite patches that can be found at some points on the surface. But, at the same time, it would have created that covering. Initially, it was thought that this covering was made of graphene, but the data currently in the hands of NASA reveal that it is another material that covers the planet: diamond.
Getting to know Mercury better
To make this discovery, an estimate was made of the pressure of the planet’s core and mantle, and Mercury’s carbon content was taken into account. Of course, they also took as a reference the geophysical data provided by NASA’s Messenger mission, without which they possibly could not have reached these conclusions.
The planet’s mantle has previously been found to be thicker than previously thought, so it’s great to see how we’re slowly learning more about Mercury. The Messenger mission, however, finished its work in 2015 after spending several years orbiting Mercury since its launch in 2004. It was the first spacecraft to orbit the planet and not only mapped it completely, but was also responsible for discovering water ice and other important components.
To test all the data, the team of scientists leading the project has run simulations in their laboratories on Earth to see how the temperatures and pressures of Mercury act. This has provided them with enough data to come up with several theories that could explain the presence of this diamond mantle around the planet. They mention that, in one of their theories, the planet had a completely liquid core that crystallized over time.
This would explain why the diamond layer is so thick, since if it had only been formed as a result of the lava oceans it would be much thinner. The diamond would have moved over time towards the core of the planet and its mantle until it formed a 1 kilometre layer that would have grown over the years. According to them, the formation of this diamond layer was also helped by the fact that Mercury has more carbon than oxygen, which, added to its proximity to the Sun, would have led to this curious newly discovered characteristic. Based on this, they now hope that, using this information as a reference, they can continue solving mysteries about the planet.
