Solar eclipse ended the war and shook the gods – 04/08/2024 – Science

In the spring of 585 BC in the Eastern Mediterranean, the Moon appeared out of nowhere to hide the Sun, turning day into night.

Back then, solar eclipses were shrouded in frightening uncertainty. But it was said that a Greek philosopher had predicted the disappearance of the Sun. His name was Thales. He lived on the coast of Anatolia — now in Turkey, then a cradle of early Greek civilization — and was also said to have acquired his unusual power by abandoning the gods.

The eclipse had an immediate impact on the world. The Medes and Lydian kingdoms had been fighting a brutal war for years. However, the eclipse was interpreted as a bad omen, and the Armies quickly lowered their weapons. The terms of the peace included the marriage of the daughter of the king of Lydia to the son of the king of Mede.

Thales’ prediction had a more lasting impact, with his reputation gaining strength over the centuries. Herodotus told of his prediction. Aristotle called Thales the first person to understand nature. The classical era of Greece honored him as the foremost of the seven sages.

Today, the tale illustrates the fear of the ancients about the disappearance of the Sun and the great surprise that a philosopher knew this in advance.

The episode also marks a turning point. For eons, solar eclipses were feared as omens of calamity. Kings trembled. Then, about 2,600 years ago, Thales led a charge that replaced superstition with rational eclipse prediction.

Today, astronomers can determine the moment when the Sun will disappear this Monday (8) in a strip of North America. Weather permitting, the astronomical event is expected to become the most watched in American history.

“Everywhere you look, from modern times to the past, everyone wanted predictions” of what the heavens would hold, according to Mathieu Ossendrijver, an Assyriologist at the Free University of Berlin. According to him, the Babylonian kings “were terrified of eclipses.” In response, rulers watched the sky in an attempt to anticipate ill omens, appease the gods, and “strengthen their legitimacy.”

According to reports, Thales initiated the rationalist vision. He is often considered the world’s first scientist, the founder of a radical new way of thinking.

Long before Thales, the ancient landscape carried successful signs of eclipse prediction. Modern experts say Stonehenge — one of the world’s most famous prehistoric sites, whose construction began about 5,000 years ago — may have been able to warn of lunar and solar eclipses.

Although the ancient Chinese and Mayans recorded the dates of eclipses, few ancient cultures learned to predict disappearances.

The first clear evidence of success comes from Babylon.

From about 750 BC, Babylonian clay tablets bear accounts of eclipses. Based on records of the phenomenon, the Babylonians were able to discern patterns of celestial cycles and eclipse seasons. Members of the court could then warn of divine displeasure and try to avoid punishment, such as the fall of a king.

The most extreme measure was to employ a scapegoat. The substitute king fulfilled all the usual rites and duties, including those of marriage. The substitute king and queen were then killed as sacrifices to the gods, with the true king being hidden until the danger had passed.

Initially, the Babylonians focused on recording and predicting eclipses of the Moon, not the Sun. The different sizes of eclipse shadows allowed them to observe a greater number of lunar disappearances.

Earth’s shadow is so large that, during a lunar eclipse, it blocks sunlight from a huge region of outer space, making the satellite’s disappearance and reappearance visible to everyone on the night side of the planet. The size difference is reversed in a solar eclipse. The relatively small shadow of the Moon makes observation of totality — the complete disappearance of the Sun — quite limited in geographic range.

Thus, the Babylonians, by chance, focused on the Moon. They then realized that lunar eclipses tend to recur every 6,585 days — or approximately every 18 years. This has led to advances in predicting the probabilities of lunar eclipses, despite knowing little about the cosmic realities behind the disappearances.

“They could predict them very well,” said John M. Steele, a historian of ancient science at Brown University and a contributor to the book “Eclipse and Revelation.”

It was Herodotus who, in “The Stories”, told about Thales’ prediction of the solar eclipse that ended the war. He said the ancient philosopher had brought forward the date of the Sun’s disappearance “within the year” of the actual event.

However, modern experts, starting in 1864, cast doubt on the ancient claim. Many saw it as apocryphal. In 1957, Otto Neugebauer, a historian of science, called it “very doubtful.”

In recent years, the claim has received new support. The updates are based on knowledge of the types of observational cycles that Babylon pioneered. The patterns are seen as something that allowed Thales to make solar predictions that, if not certainties, could be successful from time to time.

If Stonehenge can do it occasionally, why not Thales?

Mark Littmann, an astronomer, and Fred Espenak, a retired NASA astrophysicist specializing in eclipses, argue in their book, “Totality,” that the date of the wartime eclipse was relatively easy to predict, but not its exact location. As a result, they write, Thales “could have warned about the possibility of a solar eclipse.”

Leo Dubal, a retired Swiss physicist who studies artifacts from the ancient past and recently wrote about Thales, agreed. The Greek philosopher could have known the date with great certainty while being uncertain about the places where the eclipse would be visible, such as on the front lines of war.

Over the centuries, Greek astronomers learned more about the Babylonian cycles and used this knowledge as a basis for advancing their own work. What was marginal in Thales’ day became more reliable, including prior knowledge of solar eclipses.

The Antikythera mechanism, an incredibly complex mechanical device, is a testament to Greek progress. It was made four centuries after Thales, in the 2nd century BC, and found on a Greek island in 1900. Its dozens of gears and dials made it possible to predict many cosmic events, including dates of solar eclipses.

For centuries, even during the Renaissance, astronomers continued to refine their eclipse predictions based on what the Babylonians had observed. The 18-year cycle, said Brown University’s Steele, “had a really long history because it worked.”

Then came a revolution. In 1543, Nicolaus Copernicus placed the Sun, not the Earth, at the center of planetary movements. His discovery led to detailed studies of the mechanics of eclipses.

The star was Isaac Newton, the towering genius who in 1687 discovered the Universe with his law of gravitational attraction. His discovery made it possible to predict the exact paths of not only comets and planets, but also the Sun, Moon and Earth. As a result, eclipse predictions have increased in accuracy.

Today’s experts, using Newton’s laws and banks of powerful computers, can predict the motions of stars millions of years into the future.

But closer to home, they have difficulty making eclipse predictions over such long periods. This is because the Earth, Moon and Sun are in relative proximity and therefore exert comparatively strong gravitational “pulls” on each other, which subtly change in strength over the eons, slightly altering planetary rotations and positions.

Despite such complications, “it is possible to predict eclipse dates more than 10,000 years into the future,” said Espenak, the former NASA expert.