It cracks me up how we humans, with our pitifully short lifetimes, make the default assumption that everything has always been the way it is now, and should always be that way into the future. That's so dumb.
The surface temperature changes. The climate/weather changes. The ocean currents change. The continents drift around. Right under our thin-thin crust is magma -- "liquid hot magma" -- that spurts out through cracks and shoots into the air and makes island chains. The model of the earth that has a solid inner core and a soft outer core and a softer mantle is too simplified and the boundaries aren't fixed. The magnetic poles move around at timescales we can track, and there's lots of evidence that from time to time they reverse.
We live on a geomagnetic dynamo. Should we be the least bit surprised that gravity is dynamic?
Anyway, great post, thanks again!
Thanks!