I suspect somebody plugs the vertical movement data into a model and microseconds come out.
Bob On Mar 15, 2011, at 7:07 PM, Neville Michie <[email protected]> wrote: > One simple calculation is the ratio of the total rotational energy of the > planet (which is simple to calculate) to the energy release of the earthquake. > The magnitude of the earthquake probably has a relation to the total energy > release. This must put an upper limit on the change of time. > Since the mass of the planet is conserved, we have the moment of the planet > and its rotational energy as variables. > The radius of the planet may have changed, so we will eagerly wait to see the > rate of change of the rotation rate. > It is also possible that the earthquake only caused a phase shift in the > planets rotation, i.e. the rate of rotation stays the same but the time of > sunrise has shifted slightly. > Maybe that someone who knows about these things will tell us more. > cheers, > Neville Michie > > > On 16/03/2011, at 12:29 AM, jimlux wrote: > >> On 3/15/11 6:20 AM, jimlux wrote: >>> On 3/15/11 1:49 AM, Chris H wrote: >> >>>> I hear in the Media that the earth quake sped the rotation of the earth >>>> up.. >>>> Can anyone confirm this? >>>> >>> >>> No.. the magnitude of the change is parts in 1E11 or thereabouts. >>> >>> Regular old tidal drag slowing is bigger, and that's what mostly >>> contributes to leap seconds. >>> >> >> >> Another, potentially easier to detect, effect is that the axis of rotation >> of the earth might have shifted. >> >> An interesting question is whether earthquakes always lead to a speeding >> up... Off hand, I would think that the general tendency is for the >> gravitational forces to make the earth more smooth, which would probably >> mean that the moment of inertia decreases (speeding up the rotation). (that >> is, mountains fill ocean trenches in the long run). >> >> On the other hand, rotational forces make the earth more oblate, which >> increases the moment of inertia. I seem to recall that the inital >> predictions of oblateness were made by assuming that there's an equilibrium >> between gravitational forces pulling in and rotational forces pulling out. >> >> >> And this doesn't even get into the fact that the earth is somewhat pear >> shaped: wider south of the equator than north. ( most certainly not a banana >> shape as reported by Sir Bedivere, but what would a medieval experimenter >> with swallows know anyway) >> >> _______________________________________________ >> time-nuts mailing list -- [email protected] >> To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts >> and follow the instructions there. > > > _______________________________________________ > time-nuts mailing list -- [email protected] > To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts > and follow the instructions there. _______________________________________________ time-nuts mailing list -- [email protected] To unsubscribe, go to https://www.febo.com/cgi-bin/mailman/listinfo/time-nuts and follow the instructions there.
