First, let's create the Earth-Moon container:
- In Hierarchy, create a new empty object under SolarSystem, named Earth-Moon and reset its Transform.
- Move Earth as a child of Earth-Moon.
- Set their positions as follows: SolarSystem (0, 0.75, 0), Earth-Moon (0, 0, 0), and Earth (0, 0, 0).
The resulting hierarchy is shown in the following screenshot: