What geometrical effect do gravitational waves cause on a circle of freely floating test particles as they pass?

Answer

The particles are squeezed along one axis while being stretched along the perpendicular axis, and this effect reverses.

As a gravitational wave passes, test particles exhibit a rhythmic pattern: they are squeezed along one axis while simultaneously being stretched along the perpendicular axis, then the stretching and squeezing reverse.

What geometrical effect do gravitational waves cause on a circle of freely floating test particles as they pass?
propagationspacetimewavegravitational wave