Secret
It would be hard to find a line of symmetry on a moon, as it is likely to be irregularly shaped.
It is the displacement method.
Google "Archimedes' Principle" and see if that gives you a clue...
Mass divided by Volume = Density. Or use the displacement method for an irregularly shaped object.
The apple was irregularly shaped
A balance is used to measure the mass of an irregularly shaped solid.
The volume of an irregularly shaped solid can be measured by placing the solid in a known quantity of water in a container with measurement markings. Take the new volume and find the difference between this and the old volume. This is the volume of your irregularly shaped solid.
Finding the center of gravity of an irregularly shaped object can be done using the plumb line method.
square
batholiths
Poikilocyte
asteroid
Lump
A lump
Tight
batholiths