Still more evidence for a magnetic connection are the statistics of auroral observations. Elias Loomis (1860) and later in more detail Hermann Fritz (1881) established that the aurora appeared mainly in the “auroral zone”, a ring-shaped region of approx. radius 2500 km around the magnetic pole of the Earth, not its geographic one. It was hardly ever seen near that pole itself. The instantaneous distribution of auroras (“auroral oval”, Yasha Feldstein 1963) is slightly different, centred about 3-5 degrees nightward of the magnetic pole, so that auroral arcs reach furthest equator-ward around midnight.

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