RobertBast
Hi there,

I compared every 6.5+ magnitude earthquake listed at USGS since 1973, with the 90 lunar eclipses that occurred during the same period, and found that large earthquakes are more likely to happen within a day of a lunar eclipse (the day of the eclipse, the day before and the day after).

(there's two tabs - the data, and where I got the data from)

1720 earthquakes of 6.5+ magnitude in 14031 days equals 1 in every 8.15 days

45 earthquakes of 6.5+ magnitude from within one day of 90 eclipses, from 270 days = 1 in every 6

Could I be onto something? Could the gravitational tug-of-war which is surely at its strongest during a lunar eclipse, be enough to trigger some earthquakes?

Regards,
Robert Bast
Melbourne, Australia
Robittybob1
The maths tells the story. I had read this was known already but the effects wasn't as great.
It became an issue as in NZ they were having a series of earthquakes close to Christchurch. A guy called Ken Ring was saying that he predicted a major Earth quake there associated with the full moon and when the moon was at its closet to the Earth. The significant aftershock didn't happen on the day predicted but a couple of days later.
Quantum_Conundrum
It's a 35.8% increase in frequency, which seems pretty significant to me.

Additionally, the basic notion that the gravitational and tidal forces aligning may increase the frequency of quakes seems simple enough and straightforward enough. Same idea is used to try to explain how liquid water might exist on the moon of outer solar system planets, etc.

So similar versions of the theory is actually already being applied in astronomy and planetary dynamics for other reasons anyway.

Perhaps its to nobody's benefit to panic on every Eclipse or Perigee.

Speaking of which, what were the statistics for "Perigee".

You only gave "Eclipses".

Apogee?

What were the statistics for Eclipses on a perigee, or eclipses on an apogee?

I would expect that with a long enough record, eclipses on a perigee should be the most likely of all to produce an Earthquake, while non-eclipsed apogees should be the days least likely to produce an Earthquake.

That is, if you had the proof of Apogees having a reduced likelihood of quakes relative to the average, it would it would reinforce the proofs.

Moreover, if you compared the days which were farthest from being an eclipse, which are harder to track because nobody typically mentions them, then you should also find a markedly lower number of quakes on such a day...i.e. when the Moon is offset by 90 degrees from an eclipse event...