"After these seven Root Races, the Earth will become a new moon. In the first round, our Earth was created with matter from the mental plane. In the second round, our Earth condensed into substance of the astral plane. In the third round, our Earth condensed into an ethereal form; and in this present, fourth round, the Earth crystallized into a physical and chemical form. It is urgent to know that the physical-chemical Earth evolves according with the laws of planetary karma. The future fifth round will develop in the ethereal world, the sixth round in the astral world, and the seventh round in the mental world. Afterwards, the great cosmic night will arrive." - Samael Aun Weor, The Kabbalah of the Mayan Mysteries