The great mythological figure Cuchulainn was probably a comet that very nearly smacked into the Earth in AD 540. Descriptions of Cuchulainn and his father, Lugh, are not unlike how one might describe a near-miss comet passing so close that it first filled the sky with fireworks then choked it with dust and rubble.
This remarkable theory was put forward yesterday by a Belfast scientist, Prof Mike Baillie of Queen's University. He was addressing a Festival of Science session which discussed just how quickly dramatic and deadly changes in climate could occur. He acknowledged the incongruity of a scientist blending hard experimental fact with mythology. This was because there was plenty of scientific evidence for stunning climatic changes around the year 540, but remarkably little about such changes in the written historical record.
Prof Baillie is a specialist in dendrochronology, the study of tree rings which can reveal hidden information from the past about climate and temperature. In kind years with good weather the tree grows rapidly and lays down a thicker annual ring. In harsh conditions the ring is narrow. "We can date tree rings intricately well and can compare them with history," he stated. And the ring for AD 540 stands out as exceptional, as shown by independent analysis around the world. "We don't know what caused it. There is a hypothesis there was a super-volcano."
There was little supporting evidence from ice cores however, for an eruption that blocked the sun with ash, he added. "The better line is, in my view, we had some type of interaction with a comet. And in my view it probably started the Dark Ages." There was very little written at the time about such an event, but Prof Baillie believes it is there, only hidden.
"It is nearly impossible to get historians to deal with this." He cited research on comets published by Prof Mark Bailey of Armagh Observatory and colleagues in which they postulated that the Dark Ages could have begun after the Earth ran into "a swarm of material" left behind by a close passing comet. They estimated that a period of high swarm activity occurred sometime between AD 400-600. Mythology also yielded clues, Prof Baillie suggested. Cuchulainn, during his infamous "battle rage" as described in the Tain Bo Cuailgne, was said to send a jet of blood spouting from his head, forming "a magic mist of gloom" that covered the whole sky. Lugh appeared "with a long arm" (Lamfhada) and "of the mighty blows" (Loinnbheimionach), Prof Baillie said. Lugh's description could immediately be applied to that of a comet and its tail. Cuchulainn's battle rage, said to include impressive fireworks, might approximate the spectacular displays caused in the sky had a comet passed close enough to Earth to penetrate its magnetosphere.