Why not use the same solar sail to measure space-time itself? Basically the Space-Time Cube would be three layers on each face of the cube with sensors built into each four point connection. The Space-Time Cube is then deployed where any fluctuations would register as movement and recorded. The other two layers would record the second and third movements of Space-Time to generate a Tri-Layer resulting in the first 3D Mapping of Space-Time. If Space-Time functions like I think it does then the sheets of cube should record data similar to how a group of people make waves using a bed sheet. I remember how that was fun growing up..until someone got the flea brained idea to toss me into the air higher than they should have....where did he go?