Wilcox (1973)
brings together a number of threads of information, all indicating that the solar magnetic field is essentially monopolar for a few months near solar minimum.
(1) The photospheric field observed with the Mount Wilson magnetograph was predominantly directed away from the Sun during the first third of 1965. The evidence is against a simple instrumental bias, and against the existence of polar fields that would balance the total flux. Crimean magnetograph observations showed the same result (Severny, 1968).
(2) The interplanetary field detected from spacecraft near Earth in 1965 showed that only a narrow sector of field was directed toward the Sun; the extended solar field in the plane of the ecliptic was also predominantly away from the Sun at this time.
(3) Svalgaard (1972) studied the large-scale structure of the extended solar magnetic-field polarity over four activity cycles, the polarity being derived from characteristic responses of the high-latitude geomagnetic field. He found an epoch of predominantly outward polarity to be a typical feature near solar minimum.
2. A Magnetically Charged Sun
On the basis of classical electromagnetics, one rejects outright the idea of unbalanced magnetic flux from the Sun, for all earthly experience confirms the divergence-free nature of magnetic field. There is a case, however, put forth by Schwinger (1969), for the existence of magnetic charge that is analagous to electric charge and appears symmetrically in Maxwell's equations. This magnetic charge explains the quantization of electric charge, relates the concepts of spin and hypercharge to that of charge, permits the existence of certain fractional electric charges and provides a dynamical mechanism for the observed weak violation of charge-parity symmetry. Schwinger christens the dually (electric, magnetic) charged particle 'dyon', determines the magnitude of unit magnetic charge (822 times that of electric charge, 3.95 x 10-7 esu), and