Gravity

BBC article on the ESA Goce satellite project.

Imagine flooding the earth so no land would show.  If the earth were a sphere of uniformly distributed mass (or for your sticklers or mathematicians, mass distributed with spherical symmetry) then the water's surface would also be a sphere.

But, change the mass distribution so that it is lumpy and the water would re-distribute itself so that the lines of gravity passing through it will be normal to the surface (perpendicular to a tangent line drawn at the surface at that point)

The Earth is very lumpy.  We knew that for some time.  Now we have an accurate map of that virtual surface that would be...

Thanks ESA and CERN for keeping science going on the other side of the pond!