A team of researchers from Universities of Warwick and Aix-Marseille have stumbled upon an extremely interesting exoplanet. While it is about the size of Earth, it is the densest planet ever seen of the type. This makes it less similar to our planet, and more similar to Mercury. By discovering more about this dense exoplanet, we might decode the mysteries of Mercury’s formation.
The dense exoplanet is more similar to Mercury
This newly discovered planet received the name K2-229b. It had about the same size as Earth, so researchers expected it should share some properties with our planet. However, it turned out it was an extremely dense exoplanet, and it was a lot more similar to other dense cosmic bodies, like Mercury.
Also, for the first time, researchers measured the mass of the planet. This is how they saw it was different from Earth, as it had about 2.5 times the mass of our planet. However, what does this mean? The density of a planet is given by the materials it’s made of. In this case, the dense exoplanet contains more metals than rocks in its composition.
Scientists are now looking for a theory to explain its formation
This is quite interesting, and left scientists pondering on three possible ways these planets could have formed. The first hypothesis argues that these cosmic bodies might have had more rocky material, but repeated collisions reduced it. However, the explanation might be about the cloud that surrounded them at their formation.
Depending on what this cloud contains, the planet gets rockier or more metallic. If the cloud and the governing star didn’t produce too much rocky material, then the dense exoplanet ended up containing more metal. The last hypothesis claims that radiation destroyed all those rocks just when the exoplanet was in the middle of its formation.
At the moment, it’s hard to say which hypothesis is the real one. However, there must be something that will make it possible for an Earth-size dense exoplanet be similar to Mercury. Other details on the study have been published in the journal Nature Astronomy.
Image source: NASA