An ancient Chinese text reveals the oldest known record of the aurora borealis

There is rarely time to write about every great science story that comes our way. So this year, we’re once again running a special “The Twelve Days of Christmas” series of posts, highlighting one science story that fell through the cracks in 2022, every day from December 25th to January 5th. Today: A new analysis of an ancient Chinese text has revealed the first candidate diagonal aurorae to date, predating the earliest by three centuries.

A pair of researchers located the oldest description of the aurora borealis candidate yet in an ancient Chinese text, according to one of the researchers. april paper Published in the journal Advances in Space Research. The authors peg the possible date of the event to either 977 or 957 BC. The next oldest description of the aurora borealis is found on Assyrian cuneiform tablets dated between 679-655 BC, three centuries later.

as we are I mentioned earlierthe amazing shifting effects of the so-called Northern Lights (or Southern Lights if you’re in the Southern Hemisphere) are the result of charged particles from the Sun being hurled at the planet Earth. magnetosphere, where they collide with molecules of oxygen and nitrogen – an interaction that excites those molecules and makes them glow. The aurora borealis usually appear as shimmering bands in the sky, in hues of green, purple, blue, and yellow.

There are different types of auroral displays, such as a ‘diffuse’ aurora (a faint glow near the horizon), a rare ‘picket fence’ and ‘Sand dunes “, and “discrete aurora arcs” – the more intense variety, which appears in the sky as shimmering curtains of light. Discrete aurorae arcs can be so bright, it is possible to read a newspaper by their light. Such was the case in August and September 1859, when there was a great geomagnetic storm – aka carrington event, the The biggest ever—which produced dazzling aurorae visible across the United States, Europe, Japan and Australia.

the Bamboo Annals It is a historical account of ancient China, written on bamboo slats, and starting from an era Yellow Emperor And passes through the so-called Warring States period (5th century – 221 BC), when the rival states engaged in intense competition. finished when Qin state states united. The original text of Bamboo Annals Buried with King Xiang of Wei, who died in 296 BC, it was not discovered until 281 AD, thus surviving Emperor Qin Shi Huang Burn books In 212 BC (not to mention hundreds of Confucian scholars were buried alive).

Zoom in / Various fragments of Bamboo Annals.

MA van der Sluijs & H. Hayakawa, 2022

The original text consisted of 13 manuscripts that were lost during the song strain (960-1279 AD). There are two versions of the program Bamboo Annals still in existence. One is known as the “current text”, and consists of scrolls that were printed in the late sixteenth century. Many scholars believe this text to be a forgery, given the many discrepancies between its text and parts of the original quoted in ancient books, although some scholars have argued that some parts may be faithful to the original text. The other version is known as the “Ancient Text,” and was pieced together by studying the above-quoted fragments found in ancient books, especially two books dating from the early eighth century CE.

Independent researcher Marinus Anthony van der Slweg and Hisashi Hayakawa of Nagoya University relied on the ancient text for their new analysis. This text describes the appearance of a “five-colored light” visible in the northern part of the night sky near the end of an era King Zhao affiliate Zhou family. Aurorae tend to only be visible in the polar regions because the particles follow Earth’s magnetic field lines, which radiate from the vicinity of the poles. But strong geomagnetic storms can cause auroral ovals to stretch out to lower latitudes, often accompanied by multicolored lights. According to the authors, during the 10th century BC, Earth’s north magnetic pole was about 15 degrees closer to central China than it is today, so people there may have witnessed such displays.

While this is technically an uncertain candidate aurora, the authors write: “The explicit indication of nighttime observations excludes daytime manifestations of atmospheric optics, which sometimes mimic candidate events.” Furthermore, “the occurrence of a multicolored phenomenon in the northern sky during the night is consistent with auroral displays visible in mid-latitudes.” According to van der Sluijs and Hayakawa, the current 16th-century text translation of the passage in question described the event as a “comet”, not as a “pentachromatic light”, and for this reason the candidate aurora has not yet been identified.

DOI: Advances in Space Research, 2022. 10.1016/j.asr.2022.01.010 (About DOIs).