Ancient Chinese Writing Mentions a Celestial Event Which Might Be the Oldest Known Reference to a Potential Aurora

Historians are not only known to record historical events, but are also keen observers of the sky, or so it says. Chinese historical documents, which told the history of China from the earliest legendary time to the 4th century BCE, mentions in its text a celestial phenomenon that turns out to be the oldest known reference to a potential aurora.

According to SciTech Daily, a five-colored light" seen in the northern region of the sky on a night near the finality of King Zhao's reign was the earliest record of a candidate aurora found in Chinese Annals. The celestial event detailed in the journal Advances in Space Research turns out to be "the oldest known reference to a candidate aurora" and predates the previous reference of an aurora by three centuries.

The study led by Marinus Anthony van der Sluijs, an independent researcher based in Canada, and Hisashi Hayakawa from Nagoya University, report their extended knowledge of solar eruptions in the millennial time scale.

A "Spectacle of Multiple Colors"

The old Chinese document called the Bamboo Annals, or Zhushu Jinian in Mandarin provided surprising new insights, including the record of the "five-colored light" which was found to be consistent with a large geomagnetic storm.

While the exact year is unknown, researchers suspect that this set of Chinese court records in bamboo slips hidden in a tomb six miles southwest of the present-day city of Weihui was written in either 977 B.C.E. or 957 B.C.E., providing the earliest described aurora, Live Science reported. According to the team, the mid-latitude aurora is so sufficiently bright that it can present a spectacle of multiple colors.

Comparing this historical record much closer to our time, the north magnetic pole was inclined toward the Eurasian continents during the mid-tenth century B.C.E. which means that it was 15 degrees closer to central China than it is now. Therefore, individuals in central China could have witnessed the vibrant geomagnetic storm or at times of "significant magnetic disturbance".

World's Earliest Datable Record of an Aurora

While there had been several holders of this distinction, it was only that the chronicle entry of the "five-colored light" was revealed barely two years prior that this finding took a while to recognize. Nevertheless, it is impressive that popular accounts of the northern lights can be traced back this far.

Other than that, such historical information is also useful for other purposes including modeling long-term space weather variability and solar activity over timeframes ranging from decades to millennia, beyond the chronological coverage of instrumental observations. In addition, understanding these variations can help society prepare for potential future large-scale solar eruptions and the disruption to technological infrastructure that they may bring, according to the study.

To this date, the record is now the only known historical reference to a space weather event before the Homeric Grand (Solar) Minimum (810 - 740 BCE), preferably be called the Neo-Assyrian Grand Minimum to honor Homer's controversial historicity and dates.