Alaska's Auroras the Best?

Flights of instrumented aircraft over Alaska and south of New Zealand have shown that the southern aurora can duplicate the boreal aurora. Also, the flights have shown that the auroras over Alaska are typically 20-30% brighter.

Putting this observation and others together, scientists at the Geophysical Institute have concluded that the aurora over Alaska and eastern Siberia is probably brighter than over eastern Canada, Iceland and Northern Scandinavia.

An explanation for the difference in brightness with longitude comes from the knowledge that the earth's magnetic field strength varies with longitude. The magnetic field strength helps determine how many electrons and protons can enter the earth's atmosphere to cause the aurora. The more charged particles entering, the brighter the aurora.