Based on the physical model of a known mathematical problem, which consists in covering a geometric shape with some other.
Although it will be easy to use youll realize that it will be difficult to solve ... test yourself!
Your goal is to eclipse all the moon with the smaller planets so that no part of the moon is visible.
To move a planet just drag it. When you release a planet while it covers even a little part of the moon you wont be able to move that planet anymore.
"One cloud is enough to eclipse all the moon"