reply to post by Arbitrageur
Yes, its nice to see when a questions gives an unexpected answer. I guess it has yet to be seen if instant knowledge is good for the progress of
mankind or not. I do catch myself looking up extremely basal stuff every now and then, things that people 100 year ago would know by hearth. (who had
the proper education). In this case I think it is also nice to understand why gravity is larger at the core layer edge. Had you posted that
image as first reply, I doubt I would have given it as much thought as I did now.


I went away, cleared my head, and
sat down and did the math for myself (not PLB's math, but the function describing g with depth, as it's outlined in that Wikipedia article... though,
I didn't read it until after)... g goes linearly to 0 at the center of a mass with uniform density, and g is concave parabolic for a mass with density
that decreases linearly with radial distance.