Is the Moon a Dwarf Planet now??
Is the Moon a Dwarf Planet now??
If Ceres is to now be considered to be a dwarf planet should our moon be also???
Unfortunately the IAU was only trying to clarify the definition of the term "Planet" and not moon. I would think that "Moon" will remain ambiguous until it needs clarification. To that end, the moon is still a moon as long as it orbits a planet and not the sun directly. So the only thing that can change in the course of a single lifetime is that a "Small solar system body" can become a moon if it is captured by the gravity of a planet, and a moon can become an impactor if it used to be a small asteroid or comet in a former life.
I don't know what the now accepted definition for 'dwarf planet' is, but I assume that it would have to orbit a star as opposed to a planet.
That is, there is not an object other than a star that its barycenter (rotational center) resides in. The moon's orbital center resides within Earth, I believe.
But if this is not part of the 'dward planet' definition, then I could be wrong.
the problem with classifying these according to so many rules is that you will always seem to find another object that doesn't fit any particular definition.
I wonder how this definition would be applied to binary star systems with planets.
That is, there is not an object other than a star that its barycenter (rotational center) resides in. The moon's orbital center resides within Earth, I believe.
But if this is not part of the 'dward planet' definition, then I could be wrong.
the problem with classifying these according to so many rules is that you will always seem to find another object that doesn't fit any particular definition.
I wonder how this definition would be applied to binary star systems with planets.