So I'm experimenting with the Magnet Force, and I figured it would be a good way to simulate planets orbiting stars. I got that working, and that was the easy part, since a star is more or less stationary..

But I decided to take it up another level and create a moon to orbit the planet in turn. I cannot for the life of me figure out how to make the planet's gravity Metaball follow the planet..



The green is the sun's gravitational field. Yellow is the sun. Orange is the planet's gravity field, and grey is the moon.


I figured I might try to use an expression to make the metaball take the position-in-space of the planet, then apply that to the metaball's position, but this has proven ineffective, because the planet's position is not changing with each frame: it remains at its initial position before the simulation begins:

Frame One:


Frame 32 (for example)


You'll notice that the geometry's position hasn't changed over this course. I think I understand this, as this is more about giving the initial circumstances and letting the program do its thing. The Geometry spreadsheet shows the geometry's components (vertices, etc.) as updating each frame, but I can't find anything regarding the position of the object itself.


Is this a thing? Does anyone know where I can find that information if it is?

Thanks!!