Approximately 75,000 years ago, those who Ra calls the Guardians transferred the genetic material of the third-density Mars population from its destroyed home to Earth. This was deemed to be an abridgement of free will, so a quarantine was placed around Earth by the Guardians at the start of the 75,000 year master cycle of third density. The quarantine prevents interference from entities of other densities except in two circumstances: one, the Council grants permission to break quarantine, or two, a negative entity takes advantage of the window effect.