It is not your imagination that you see Tetrahedral Shapes on the Moon, and the faint outline of such on the eroded surface of Mars. Yes, they are there, and yes, they had a purpose in the past. They are not inactive structures, with no reuse in the foreseeable future. What were they used for, and is there magic in the shape? The shape is significant, as it is functional. Large crystals have been used to boost communications by a number of alien races in Earth's past. The tetrahedral form simply provided the best focused emission, when energy was applied on all perimeter surfaces and converged in the center. This was one of the things noticed by the astonished astronauts when they disembarked on the Moon. This subject receives much press, and much speculation, as the rumors can be supported by faint images in amateur telescopes.
What alien races used this method, and whom were they communicating to? We are speaking here primarily of the inhabitants of the 12th Planet, whose hominoid form we have referred to as the Greek God form. This race was chased from Earth by the administrative authority of the Council of Worlds. They were quarantined from Earth so that the race of man could develop without undue influence. Even before the quarantine period they had established a communication post on the Moon, and they had a mining operation on Mars long before setting up on the Earth.