Scientists measured the tone of the earth in 1960 during an earthquake in Chile. Seismographs showed that the earth "rings" with deep vibrations that are exactly twenty octaves below the lowest sound that the human ear can hear. Approximately every twelve years the planets become somewhat aligned with one another. If we could hear the combination of these various tones at this time, they would most likely sound like a musical chord. Imagine--the planets are like a gigantic musical instrument resonating in the universe!