It might be of some interest to note that following Vestine's suggestion, we had incorporated the magnetic monopole (g00) as a variable in our geomagnetic field modeling programs several years ago and sometimes turn it on (allow it to assume a nonzero value) to help test our analyses. As we reported at the Bergen meeting in 1966, its value tends to hover about the level which we guess to be the accuracy of the coefficients desired and has been as low as 1 nT from the models run using only POGO data

We have also tested using the recent Magsat data and find g00 now about 3 nT for the earth. Ignoring the real possibility that we are only determining a noise figure, is there a chance that the sum of all monopoles in the earth could add up to an observable g00?