The eclipse of Lu

In our 709 BC, what is now called "China" was under the Zhou regime... sort of. Many duchies were autonomous and dynastic, rather like what Pourshariati says of Sasanian Iran. We've all heard of Song, where the old Shang survived. Another such was Lu. It seems Lu, at least, had shifted from the old Shang practice of oracle-bones and were doing astrology instead. On 17 July (Julian), their observatory at Khoɡ-Bu' saw an eclipse. By modern pinyin it's Qūfù.

To make a correction here, this is hardly the first eclipse in astrologic history. The Mesopotamia observed one in 763 BC, heralding (or underlining) the failed Tiglath-Pileser III in Assyria, albeit invisible to Chinese. We'll get to that. For another interjection of personal frustration, ScienceDaily saw fit to tell us only now, almost a year after the paper. Weak!

We know Lu's eclipse from two later records: the "Spring and Autumn" annals, in a time when the Zhou were pretty-much being ignored; and Jīng Fáng's still-later (78-37 BC) account. I think the latter ended up in "Book of Han". For Jing, all these events were (literal) ancient history, like the various Jewish Antiquities books were for the Romans. The former is taken more seriously given that Confucius himself will be born in Lu, and seems to have had a hand in preserving their annal. But the Hans' Shu adds detail of two ears around the lunar-disc. A Japanese-led quintet, including a Meng Jin presumed Chinese, believes the latter was corona.

Although everyone has accepted the date (-708\07\17) and the place (old Lu... somewhere) of this eclipse, discrepancies persisted about the exact time and place of the Qufu observatory. It seems we've pinned down that capital, correcting other estimates that it was eight kilometers away (later dukes may have moved house). On the assumption the ducal astrologers were close to the palace, the paper must adjust ΔT to run its totality over the new site. This further adjusts ΔT for the later eclipses over Lu until ~548 BC.

For the sun himself, all this validates a maximum around 709 BC, perhaps on par with 18 October 1848. This particular eclipse, of course, was invisible to the astrologers of Babylon; but as I've noted, they had others. Coronae might not have been observable for what eclipses they had 808-717 BC which is tagged the "Neo-Assyrian Minimum". Which mostly it was... for said Assyrians, between Shamshi-Adad V and Pulu that second "Tiglath-Pileser III".