We know that many planets, even the planet earth, have one or more moons that orbit around them, but have you ever wondered if it’s possible for a moon to have another heavenly body that orbits around it?


Guess what? There is a possibility for to actually happen. Juna Kollmeier, an astronomer from Carnegie Institute of Washington, and Sean Raymond, an astronomer from the University of Bordeaux, say that a moon may have its own moon. They worked on a paper to study that possibility and just released it to the public. When asked about what the moon is called, they said it could be called a Submoon or Moonmoon.

Both of these astronomers calculated the Goldilocks conditions allowing a moon to orbit its moon without being thrown off from the orbit, or without being crushed because of the pull of gravity from the planet that the moon is orbiting on.


After several assumptions were made referring to the moons’ and the submoons’ densities, they both agreed and concluded that a moon can only have its submoon if it has a radius of 1000 km or larger and if it has a wider orbit. Only these moons are capable of accommodating submoons that are proportional to 10 km and larger. Jupiter and Saturn’s moons, for instance, are capable of hosting a submoon, because of their sizes.

They also added that it is possible for a giant planet with a moon that is about the size of the planet Neptune to host a submoon. Then again, the possibility for a moon to form another moon is quite low. That’s because it would mean another heavenly body has to be thrown into the moon’s orbit with the right speed for a submoon to co-exist with the original moon.

Because of that, both astronomers finished their paper saying that they need to make further investigations or studies about the conditions which may result in a possible creation of a submoon. As soon as Raymond and Kollmeier’s paper went live, and as soon as the public found out about it, a lot of people have shown excitement. As a matter of fact, they are already calling them moonmoons.

There is no official name for the submoon yet, although people already prefer calling them moonmoons, while a minority of people liked to just call it a submoon. This resulted in a list of suggested names for the submoon, which include: second-order moon, mini moon, and nested moon. Other terms like moon squared, meta moon, and Moony McMoonface also surfaced.

What do you want the submoon to be called? Do you agree that it should be called a moonmoon, too, just like majority of people? Or do you want to just call it a submoon? Don’t hesitate to let us know about your thoughts.


Science is such a fascinating subject because there’s always something new that’s being discovered. Who would have thought that a moon can possibly have its own moon orbiting around it? If there’s a possibility for that, then there could also be a possibility for double lunar eclipse, or whatever scientists want to call it. I’m just excited to hear about the updates for this study.