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We have studied solar activity by analyzing naked-eye sunspot observations and aurorae borealis observed at latitudes below 45 ∘ . We focused on the medieval epoch by considering the non-telescopic observations of sunspots from AD 974 to 1278 and aurorae borealis from AD 965 to 1273 that are reported in several Far East historical sources, primarily in China and Korea. After setting...
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