Hi Chris - Yes I agree on the Kp index and the Sun-Moon but I was kinda hoping Lowell would be lurking and would help with this. I was trying to avoid any arguments.

A number of things from the Sun seem to affect things - flares (x-ray flux?) which have some immediate affect and then a few days later, then geomagnetic storms (CME's-Kp index) start having an effect from 0-5 days, then there are things like proton flux (I don't know what that really is) that are an anti-quake, and electron flux - if bottomed out for a few days, signals a large (6,5+) quake on the way.

That seems to be the summary of my knowledge on the matter - I did get to listen to a couple of lectures earlier this year on the Sun. There is a science called helioseismology but it studies waves on the sun.

As for the moon - well Jim Berkland and EQF seems to think there is some increased risk of seimic activity when a new or full moon exist. I think its safe to say they don't 'cause' quakes but I think there are more quakes during the period rather than not during (like 60%-40%- not neccessarily statistically significant) and not a cause - but a lot of the big ones have occurred during the windows following (then again, the widows are so large that they cover 1/2 the month!) - My personal feeling is that its a very, very small part and can't really be used for prediction but its one of those factors to kinda throw in if other things are pointing towards an event.

Canie

• helioseismology