At the end of last year, astronomers have decided that moons that revolve around other moons should have their own name. The "moon-moon" label has been proposed – and quickly ridiculed because of its idiot – but the name seems to be stuck, for better or for worse. Once this problem is solved, some have turned to another world that does not have a concrete name.
Moons that escape the gravity of their host planet and go solo can be called many things, and their etiquette often depends on their size. For particularly massive moons that stand out, the researchers have a new name: Ploonets.
In a new article published in Earth and planetary astrophysics, the researchers propose the name of "ploonet" to describe a big moon that breaks down.
"This article explores the scenario of great regular exomoonies escaping after the exchange of angular momentum by tide with its mother planet, becoming small planets by themselves," the team writes. "We call this type of hypothetical object a ploonet."
The researchers suggest that this type of world could be the result of large "hot Jupiter" exoplanets migrating to their host star. Exoplanet surveys have detected several such planets, and it is thought that they probably formed at a greater distance from their respective stars, then slowly crept inwards.
When this happens, it is possible that the change in gravitational forces will cause large moons to break free from their existing orbits and become autonomous worlds. Computer simulations have shown that this could actually happen, and in these cases, researchers think we should call them ploonets.
Remarkably, our own moon could someday become a ploonet itself. The Moon is slowly moving away from the Earth at a very slow pace, and it is possible that it will end up in a much less stable and even solo orbit. Future generations could see the birth of a board unfold before their eyes.