A team of scientists reports that they have found the oldest description of a solar storm.
Recent analyzes have found evidence of a massive solar storm around 660 BC in ice cores and tree rings.
With this data acquired, a research team in Japan and England wondered if it was possible to find traces of this episode in ancient astronomical records, and may have found traces of it in ancient Assyrian tablets.
During the 800s, archaeologists from around the world discovered thousands of tablets dating back to the Assyrian Empire in Mesopotamia, which documented stories, treatises, narratives (including the famous epic of Gilgamesh) and astrological movements.
These last writings included the observation of the planets, of phenomena such as comets and meteorites and various forecasts.
Researchers today have plumbed these astrological records for aurora-like events, referred to as "reddish luminous phenomena in the sky" and caused by the interaction between solar particles and the atmosphere. In spite of the missing dating in many of the documents analyzed, the team was able to derive at least one time range of them.
The great solar storm of 660 BC
Il paper published in Astrophysical Journal Letters identifies references to a great solar storm in documents dated from 679 BC to 655 BC. These documents tell of skies suddenly enveloped in red dairy products, or night halos.
The region ofAssiria it may seem a little too far south to see an aurora, but in the 7th century BC magnetic north was much closer to the middle east (and solar storms tend to move auroral phenomena further south).
The solar storm of 660 BC would therefore be one of the most powerful, and certainly the first ever recorded. A "bullet" of such particles could have caused a hole in the ozone layer.
If confirmed, these correlations can help Astronomers to understand a possible cyclical nature of the phenomenon of solar storms.