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Recent studies of radioisotopes in tree rings or ice cores suggest thatextreme space weather events occurred in the pre-telescope age. Observationalrecords of naked-eye sunspots and low-latitude auroras in historical documentsin pre-telescopic age can provide useful information on past solar activity. Inthis paper, we present the results of a comprehensive survey of records ofsunspots and auroras in Chinese official histories from the 6th century to the10th century, in the period of Su\'i, T\'ang, the Five Dynasties and TenKingdoms. These official histories contain records of continuous observationswith well-formatted reports conducted under the policy of the government. Abrief comparison of the frequency of observations of sunspots and auroras withthe observations of radioisotopes as an indicator of solar activity during thecorresponding periods is provided. Based on our data, we survey and compile therecords of sunspots and auroras in historical documents from variouslocationsand in several languages, and ultimately provide these as open data to thescientific community.

publications of the astronomical society of japan

Records of sunspot and aurora activity during 581-959 CE in Chinese  official histories in the periods of Su\'i, T\'ang, and the Five Dynasties  and Ten Kingdoms