Editor’s note: Roger Culver, professor emeritus of physics at Colorado State University, wrote the following article for The Conversation in May 2017. Colorado State is a contributing institution to The Conversation, an independent collaboration between editors and academics that provides informed news analysis and commentary to the general public. See the entire list of contributing faculty and their articles here.
On August 21, a total solar eclipse will be visible across parts of the United States.
As the Earth and moon sweep through space in their annual journey around the sun, the three bodies align in such a way that the Earth passes into the shadow of the moon. Observers then witness a sun that is gradually covered and uncovered by the moon’s disk – a spectacular celestial event.
But until astronomers were able to explain this phenomenon, a solar eclipse could be a terrifying event. In many cultures throughout human history, the sun was seen as an entity of supreme importance, crucial to their very existence. It was regularly worshipped as a god – Amun-Ra to the Egyptians and Helios to the Greeks – or as a goddess, such as Amaterasu for the Japanese and Saule for many Baltic cultures.
One reason the sun served as a god or goddess in so many cultures was its awesome power: Looking directly at it would severely damages the eyes, a sign of the sun deity’s wrath.
So the idea that the sun deity could be temporarily extinguished in a total eclipse inspired a number of imaginative explanations. Most involve some sort of evil entity trying to devour the sun. Such myths undoubtedly arose from the fact that during the early stages of a solar eclipse, the sun appears to have a bite taken out of it.
The various creatures include the Vikings’ sky wolves Skoll and Hati, a Chinese dragon, a Vietnamese frog and assorted Roman demons. In many cultures, it was believed that such creatures could be driven off by creating as much loud noise as possible: yelling, ringing bells, and banging pots and pans.
Perhaps the most creative version of this strand of mythologies comes from certain branches of Hindu culture. In that version, the mortal Rahu is said to have attempted to attain immortality. The sun and moon told the god Visnu of Rahu’s transgression. As punishment, Visnu decapitated Rahu.
Ever since, Rahu has sought to exact vengeance on the sun and the moon by pursuing them across the sky to eat them. Once in a while – at the time of an eclipse – Rahu actually catches the sun or the moon. In the case of a solar eclipse, Rahu slowly devours the sun, and it gradually disappears into Rahu’s throat – only to reappear from his severed neck.
In other branches of Hindu culture, the “sun eater” took the more traditional form of a dragon. To fight this beast, certain Hindu sects in India immersed themselves up to the neck in water in an act of worship, believing that the adulation would aid the sun in fighting off the dragon.
Other cultures had equally ingenious explanations for – and defenses against – a total solar eclipse. Eskimos thought an eclipse meant that the sun and moon had become temporarily diseased. In response, they’d cover up everything of importance – themselves included – lest they be infected by the “diseased” rays of the eclipsed sun.
For the Ojibwe tribe of the Great Lakes, the onset of total eclipse represented an extinguished sun. To prevent permanent darkness, they proceeded to fire flaming arrows at the darkened sun in an attempt to rekindkle it.
Amidst the plethora of the myths and legends and interpretations of this strange event, there are seeds of understanding about their true nature.
For example, the famed total solar eclipse of May 28, 585 B.C., occurred in the middle of a battle between the Medes and the Lydians in what is now the northeast region of modern-day Turkey. The eclipse actually ended the conflict on the spot, with both sides interpreting the event as a sign of the displeasure from the gods. But based on the writings of the ancient Greek historian Heroditus, it’s thought that the great Greek philosopher-mathematician Thales of Miletus had, coincidentally, predicted its occurrence.
Chinese, Alexandrian and Babylonian astronomers were also said to be sophisticated enough to not only understand the true nature of solar eclipses, but also to roughly predict when the “dragon” would come to devour the sun. (As with much knowledge back then, however, astronomical and astrological findings were relayed only to the ruling elites, while myths and legends continued to percolate among the general population.)
Advances in modern astronomy have given us detailed explanations for solar eclipses, to the extent that their time and location can be predicted centuries into the future and reconstructed from centuries ago.
Of course, mythologies surrounding total solar eclipses still exist today. Some conspiracy theorists say this year’s eclipse will cause the end of the world – perhaps a testament to the endurance of the superstitious side of the human psyche.