98 citations · 899 across the 28 of their papers we have counts for
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Records of sunspot and aurora activity during 581-959 CE in Chinese official histories in the periods of Suí, Táng, and the Five Dynasties and Ten Kingdoms
Harufumi Tamazawa, Akito Davis Kawamura, Hisashi Hayakawa +3
Recent studies of radioisotopes in tree rings or ice cores suggest that extreme space weather events occurred in the pre-telescope age. Observational records of naked-eye sunspots…
Historical Auroras in the 990s: Evidence for Great Magnetic Storms
Hisashi Hayakawa, Harufumi Tamazawa, Yurina Uchiyama +5
Recently, a significant carbon-14 enhancement in the year 994 in tree rings has been found, suggesting an extremely large cosmic ray flux event during a short period. The origin of…
Earliest Datable Records of Aurora-like Phenomena in the Astronomical Diaries from Babylonia
Hisashi Hayakawa, Yasuyuki Mitsuma, Yusuke Ebihara +4
The Astronomical Diaries from Babylonia (ADB) are an excellent source of information of natural phenomena, including astronomical ones, in pre-Christ era because it contains the re…
The earliest drawings of datable auroras and a two-tail comet from the Syriac Chronicle of Zūqnīn
Hisashi Hayakawa, Yasuyuki Mitsuma, Yasunori Fujiwara +7
People have probably been watching the sky since the beginning of human history. Observers in pre-telescopic ages recorded anomalous events and these astronomical records in the hi…
East Asian Observations of Low Latitude Aurora during the Carrington Magnetic Storm
Hisashi Hayakawa, Kiyomi Iwahashi, Harufumi Tamazawa +6
The magnetic storm around 1859 September 2, caused by so-called Carrington flare, was the most intense in the history of modern scientific observations, and hence is considered to…