Cover image. Historically the first connection to be established between the solar cycle and the terrestrial environment is that aurorae are most common at, or just after, a solar maximum. However this conclusion was based on the infrequent huge auroral storms which reach low latitudes, while aurorae are a nightly occurrence at high latitudes. An analysis of the global occurrence rate of intense aurorae shows that, surprisingly, under conditions of darkness global auroral frequency is independent of the solar cycle, while under sunlit conditions it is actually anti-correlated with the solar cycle. [Letters, p. 342; News and Views, p. 312]. On the cover, photographs taken in and around Fairbanks, Alaska, by Jan Curtis, Geophysical Institute, University of Alaska.

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