Scientists have discovered that even faint gravitational tug of the sun and moon can set off tremors deep underground, confirming the thousands of years old belief of astrologers.
The American researchers, who studied the San Andreas Fault - the infamous crack in the ground which triggered the 1906 San Francisco earthquake, found the same gravitational tugs that create tides, also trigger small tremors that originate around 15 miles below the ground.
The report, which will come in print in journal Nature, said, although the pull of planetary objects is too weak to set off a full blown quake but the findings suggest that they could set in motion a chain of events, leading to devastation on the surface, the Daily Mail said.
Dr Roland Burgmann, a professor of earth and planetary science at University of California, Berkeley, said: "Tremors seem to be extremely sensitive to minute stress changes".
"Seismic waves from the other side of the planet triggered tremors off the coast of Washington state after the Sumatra earthquake last year, while the Denali earthquake in 2002 triggered tremors on a number of faults in California," Burgmann said.
"Now we also see that tides - the daily lunar and solar tides - very strongly modulate tremors".
American earthquake experts compared records of 2,000 small tremors in the Parkfield region 170 miles north west of Los Angeles with the movement of the sun and moon over eight years.
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