In US2, will we be able to edit the strength of the object? Meaning we could make cubes the size of earth and they wouldn't collapse into spheres? Or make spheres that don't bulge when they spin? Would be a very cool feature.
Tethers, ropes between bodies, are intended to have real structural strength, so you can select to use steel or spider silk or...
For planets, its a different issue, since currently planets are spheres and therefore not deformable.
When SPH is completed for planetary simulations, it will initially be for larger bodies which behave as if liquid, but later we may add smaller objects, such as asteroids, with actual material strength simulated with SPH.
Nb. since SPH is commonly mentioned, it is in fact not some silver bullet used for any physics which should look cool. It is only the method of choice because it easily supports fragmenting and large deformations.
Nb² the tethers are 1D finite elements