[steve86]

Slightly (but not much) OT but I just toured Caltech's LIGO observatory at Hanford. LIGO stands for Laser Interferometer Gravitational-Wave Observatory. Very interesting. This thing can pick up the collective influence (vibrations) of waves breaking on the coast even though it is 300 miles away!

http://www.ligo-wa.caltech.edu/

[steve86]

pick up...waves breaking on the coast even though it is 300 miles away!

Not to mention collapsing black holes 300 million light years away (or whatever -- they are still tuning it and have not yet identified an actual gavity wave).

[Domestic Church]

Can it pick up deep gravitational changes in the crust or below it? Any new maps ?