Books and papers
Where we read it, so anyone can check.
Bamboo Annals, 'current text' (jinben), with Shen Yue's notes, Sibu Congkan edition (Ming Tianyi Ge print), juan 1, on Chinese Wikisource; checked against the Siku Quanshu edition
The current text's sky and weather entries land on ice-core eruption years no more often than chance (p = 0.23)'Three suns rose together' in King Jie's 29th year: 1561 BC by the current text's own year count'The five planets moved in disorder, at midnight stars fell like rain, the earth shook, the Yi and Luo dried up' in Jie's 10th year (1580 BC by the current text)
Bonilla, J. A. y, Passage sur le disque solaire d'un essaim de corpuscules, vu a l'Observatoire de Zacatecas (Mexique), L'Astronomie 4 (September 1885) 347-350, with editor's note; Google scan on the Internet Archive (lastronomie03flamgoog)
Optics: a 16 cm telescope cannot hold anything farther than about 23-30 km in sharper focus than the Sun; for the Sun to look blurred on Bonilla's photo, the body was within about 0.6-4 kmBonilla's report: on his photograph 'the image of the Sun is not in focus, but that of the body is'; focused on the bodies, that night the planets were out of focus and 'only the Moon was almost in focus'
Fritz 1873, Verzeichniss beobachteter Polarlichter, Vienna. Over a thousand European aurora reports, 500 BC to 1872. The library's OCR text is saved in sources/fritz1873_polarlichter_ocr.txt
Germany: the sky toward the northwest as if burning, 1262Fiery beams around the Northern Crown (Corona Borealis), 1280Krakow: an unusual cross-shaped brightness in the sky before dawn, 5 December 1269Europe: blood-red clouds to the north on 21 September 1098, then the sky burning on 25 to 27 SeptemberFritz 1873 read: Europe has no aurora on record from 1031 to 1069
Goryeosa (History of Goryeo), original classical Chinese text on Chinese Wikisource: volumes 47 to 49 (astronomy) and 53 to 55 (five elements, the omen sections). Saved in sources/goryeosa_*.txt; dates converted with scripts/lunar_dates.py
Korean dim-Sun records track volcanic eruptions (Goryeo period, 918 to 1392)Two white vapours rose from the northwest and pierced the Sun, Korea, 27 January 1053A comet in the southern sky with a tail over 1 zhang, Korea, 25 February 1053Red vapour in the west, Korea, 19 December 1268Red vapours in the northwest and across the sky, Korea, October and December 1262Red vapour across the whole sky, then a red glow bright as day, Korea, 23 and 26 March 1278A sunspot as big as a hen's egg, Korea, 31 August 1278A heavenly dog fell in front of the Ancestral Temple, Korea, 9 March 1261The Sun was blue and without light, then red like blood, Korea, early 1258Korea: nothing in the sky in the 8th month of 1098
Guillet et al. 2023, Lunar eclipses illuminate timing and climate impact of medieval volcanism, Nature 616, 90 to 95 (open access)
Greenland-only sulfate around 1262: a northern eruption whose haze stayed lowAntarctic sulfur from the 1286 eruption starts rising in August 1285The 1286 eruption really happened in 12851261: no sky record falls in the right window, and the obvious one was already considered1229 eruption (ice cores said 1230)1286 eruption: a big sulfur signal that left the Moon brightThe Moon went as dark as a moonless night: Fujiwara no Teika on the eclipse of 2 December 1229The Moon showed yellow, red and many colours: Bartholomew de Cotton on the eclipse of 22 October 1287
Hirsch 1883, Handbook of Geographical and Historical Pathology, vol. 1 (English translation), chronological table of miliary fever (Picardy sweat) epidemics in France 1718 to 1879; outbreak years extracted to sources/picardy_sweat_years.json
Beech seed crops at Seesen (Harz, Germany), scored every year 1685-1875: Picardy sweat years follow a big crop only weakly, and just as much precede oneWhere the Picardy sweat struck (1718-1874) and where hantavirus infects people in France today (2021-2025) match only as 'north and east, not south and west'Picardy sweat: 171 dated outbreaks with their departments, 1718 to 1874
Ming History (Mingshi, finished 1739), Five Phases treatise, juan 28-30, Chinese Wikisource
Ming History records: hail in the north-west falls mostly in the 4th to 7th months (1 of 14 dated storms came by the 3rd month); hail sizes 'like goose eggs' are common; hail deaths up to about 1,000Ming China: spring snow ruins the wheat in 1453; deep snow and frozen sea in winter 1453 to 1454Ming History: 'at Qingyang it rained stones beyond counting... largest like goose eggs, smallest like foxnut seeds' (3rd month 1490), no deaths
Miyahara et al. 2022, Recurrent large-scale solar proton events before the onset of the Wolf grand solar minimum, Geophysical Research Letters 49 (free to read; read in full 25 Oct 2026; data on figshare doi 10.6084/m9.figshare.17096975)
Small radiocarbon rise, 1261 to 1262 (Miyahara 2022)Largest of the three 13th-century candidates, 1268 to 1269 (Miyahara 2022)Radiocarbon rise 1279 to 1280: three labs, three sizes1268: we thought nobody saw it, but Korea did, and it is already publishedKorea's violet glow of 25 October 1279 falls in the window for the 1279 to 1280 radiocarbon jump, and the main paper missed itA white band about 3 degrees wide stretched across the night sky, Korea, 15 February 1269Get the two paywalled papers
Yau, Stephenson and Willis 1995, A catalogue of auroral observations from China, Korea and Japan, 193 BC to AD 1770, Rutherford Appleton Laboratory report RAL-TR-95-073
1268: we thought nobody saw it, but Korea did, and it is already publishedWhite vapour shaped like a turtle, with a blue-violet vapour inside it, Korea, 18 July 1052Three red glows over Korea, October to December 1260Flickering fire in the northwest and southeast, Japan, 26 to 27 February 1263The night sky was red, China, 11 September 1277Red glow in the south, night as bright as day, Korea, 26 March 1278Violet glow in the west, its light like lightning, Korea, 25 October 1279