As people have extrapolated already, neither the unstoppable force, nor the immoveable object could ever actual exist beyond that context. Things like asteroids or the sun, have to much kenetic energy to be stopped by us, or to much mass to be moved by us, respectively. The most we can do is speculate. If I were to make such a speculation I would say that in order to stop the unstoppable force you would have to remove it's energy, no? So the immovable object would remain unmoved, and the energy of the unstoppable force would be changed to potential energy, thus contained within the immovable object would be the potential of infinite kenetic energy.