Are there compact ultra-dense objects (CUDOs) in the Universe? A few CUDO candidates are STRANGElet = fragments of neutron stars, dark matter bound objects, micro-black-hole. Could CUDOs have collided with solar system bodies and the Earth? If so: the high density of gravitating matter provides the distinct observable, the surface-penetrating puncture -- shot into, and even through, a moon or the planet. Only a fraction of the CUDO kinetic energy is damaging the entry/exit surface regions. For such exotic matter each planet or moon is a macroscopic detector accumulating signal over geological time scale. CUDOs maybe recognized by the coincident impactor hit with a singular high atmosphere volcanic eruption. Rocky objects in solar system accumulate impact scars for billions of years. Asteroid belt could harbor captured CUDOS.