This can be imagined if you take a rubber band and stretch it repeatedly. In order for heating to occur, the tidal force must change. However, it is not tidal force alone that causes tidal heating within a body. It can be seen that larger moons have greater tidal forces across them. The difference in these two forces is the tidal force felt across Europa: The force felt on the side facing away from Jupiter is: The magnitude of force felt on the side of Europa facing Jupiter is: Since the front face of Europa is closer to Jupiter than the far side, it will feel a greater gravitational force. Tidal force is the differential gravitational force felt across a body. It can be seen that as the distance between the two bodies decreases, the force increases as r 2, and as the mass of the bodies increase the force also increases. Where G is the gravitational constant, M is the mass of the more massive body (Jupiter), m is the mass of the less massive body (Europa), and r is the distance of the two bodies. The magnitude of gravitational force is defined as: The reason for its continued activity is due to tidal heating - a continual flexing and stretching of the Europa caused by the shape of its orbit and gravitational pull from Jupiter, Io, and Ganymede. However, Europa is smaller than our Moon (Table1), yet it is still geologically active. Due to its size, our Moon has had enough time to radiate its heat into space, causing its interior to cool, prohibiting geological activity. It is interesting to see moons in our solar system that are so geologically active while our own Moon is not.

Def of tidal heating