Geomagnetic Activity and Eclipse Coronae

Geomagnetic proxies (presented by various geomagnetic indices) are analyzed during the periods close to the total solar eclipses in the past. Geomagnetic variations are traces of the solar wind and interplanetary magnetic field, and of the topological evolution of large-scale magnetic fields on the Sun. We have considered historical coronal drawings in the relation to the phase of geomagnetic and sunspot cycles. It is established a coronal shape of "maximum" and "minimum" geomagnetic types. Any significant long-term trends are not detected in the changing of coronal structures. We suggest that secular increasing of AA geomagnetic indices is mainly due to the internal geomagnetic variability but it is not a response to external solar forcing.