  The sun occasionally undergoes the so-called grand minima, in which its
magnetic activity, measured by the number of sunspots, is suppressed for
decades. The most prominent grand minima, since the beginning of telescopic
observations of sunspots, is the Maunder minimum (1645-1715), when the sunspots
became rather scarce. The mechanism underlying the grand minima remains poorly
understood as there is little observational information of the solar magnetic
field at that time. In this study, we examine the records of one candidate
aurora display in China and Japan during the Maunder minimum. The presence of
auroras in such mid magnetic latitudes indicates the occurrence of great
geomagnetic storms that are usually produced by strong solar flares. However,
the records of contemporary sunspot observations from Europe suggest that, at
least for the likely aurora event, there was no large sunspot that could
produce a strong flare. Through simple theoretical arguments, we show that this
geomagnetic storm could have been generated by an eruption giant quiescent
filament, or a series of such events.
