As much as I usually am in agreement with you and your posts and comments on here, I must stray a little on this one. I was glad to see Stuart mention Steve O’Meara’s work and studies above. This is not to be brushed aside, when he and his colleagues were, at times, able to predict within minutes, the next eruption of an active volcano they were observing, based on the position of the Moon. Considering myself somewhat of an Astronomer as well, I know I am out of my field commenting on this topic, but geology had always been an interest of mine (not counting a passion/obsession with meteorites).

I had hoped for more comments from real Geologists on here, but they seem to be lacking. I am definitely NOT one, but will give it a try. When you consider the tidal forces when the Sun, Earth, and Moon are closely aligned (Full/New Moon), there are measurably higher tides. Less well known is the fact that there is a land tide as well–a gentle but measurable swelling of the land surface of the Earth, not just the liquid part. I believe the thinking/reasoning/hypothesis being that, in the case of a volcano ready to erupt, the extra pull of gravity might be enough to weaken/crack the hardened skin of surface magma holding back the liquid form below, allowing the next eruption in an active volcano, or might add to or even be the final straw that might trigger a new one. If as you posted there is evidence of tides possibly effecting earthquakes, it seems these two go hand in hand with other possible geological connections.

Before anyone discount the work of Steve O’Meara as a single source, besides being one of the founders of the respected Volcano Watch International, you might also recognize his name as the same author of several fantastic Astronomy books for Cambridge University Press (The Messier Objects, The Caldwell Objects), as a Contributing Editor to Sky and Telescope magazine, as well as being one of the finest visual observers in the world.

I’m sorry for posting this so late, but I do think I might actually have something useful to add here. I am more than open to corrections if/as needed, but not flames.

Bob

Are people forgetting that the BBC is a news organisation and not a scientific journal? Except for situations in which they are providing eye-witness reports, journalists are there to repackage and transmit information that’s provided to them by other people. Once the basic facts of an event have been established, if they then had to stop to double and triple check all the minor inconsequential details relating to what everyone told them (to avoid one or two readers throwing their toys out of the pram) then no news would ever get reported.

http://www.badastronomy.com/bablog/2006/08/09/mooning-a-volcano/#comment-42176
I agree with this earlier comment, not only about the report being balanced by not presenting the tidal relationship as indisputable fact, but also about there being some vagueness about exactly what they mean by 3 out of 47 eruptions. In a more in depth feature extra information would be needed here, but the article does not invite people to draw any conclusions based on these figures and it in no way claims that this is a large statistical sample. The numbers are clearly being provided for information purposes only.

There is no suggestion that some scientists saying that the gravitational pull of the sun and moon can influence eruptions is a conclusion that they came to by studying this volcano and these 47 erruptions alone. Therefore it makes little sense for any reader to assume that they are expected to come to the same conclusion based solely on the numbers quoted.

The International Center for Earth Tides has a long list of papers investigating the relationship between tides and volcanoes, so the BBC did not pull this idea out of the ether or shoehorn it into the article after seeing some local villager do a war dance outside their hotel room to appease the angry moon god!
http://www.astro.oma.be/ICET/icetdb/8_15.html
In the era of computers, statistics etc. all these studies were no doubt carried out using numbers!

I wonder if there would have been such an uproar if an article about a heavily pregnant elephant in Kenya happened to mention that some scientists believed the presence of a full moon might influence when elephants give birth and stated that in this particular herd 3 of the last 47 calves had been born on a full moon!

http://www.flickr.com/photos/maltloafer/214500101/

(posted on flickr ’cause my friend spends a lot of time on there, so he will get to see it)

-James
London

I also e-mailed the director of PhiVolcs. His response is at the link above.

-James
London

-Brigs
Philippines