Ancient Greeks ‘the first to spot Halley’s comet’

Friday, September 10, 2010

LONDON - Greeks in the 5th century BC were the first to spot the Halley’s comet-an event that marked a turning point in the history of astronomy.

According to ancient authors, from Aristotle onwards, a meteorite the size of a “wagonload” crashed into northern Greece sometime between 466 and 468 BC.

The impact shocked the local population and the rock became a tourist attraction for 500 years.

The accounts describe a comet in the sky when the meteorite fell.

This has received little attention, but the timing corresponds to an expected pass of Halley’s comet, which is visible from Earth every 75 years or so.

Philosopher Daniel Graham and astronomer Eric Hintz of Brigham Young University in Provo, Utah, modelled the path that Halley’s comet would have taken, and compared this with ancient descriptions of the comet.

For example, the comet was said to be visible for 75 days, accompanied by winds and shooting stars, and in the western sky when the meteorite fell.

The researchers show that Halley’s comet would have been visible for a maximum of 82 days between 4 June and 25 August 466 BC, reports New Scientist.

From 18 July onwards, a time of year characterised in this region by strong winds, it was in the western sky.

At around this time, the Earth was moving under the comet’s tail, so its debris field would have made shooting stars.

None of this proves the comet’s identity, but Graham says such major comet sightings are rare, so Halley must be a “strong contender”.

According to previous records, the earliest known sighting of Halley was made by Chinese astronomers in 240 BC.

If Graham and Hintz are correct, the Greeks saw it three orbits and more than two centuries earlier.

Plutarch wrote in the 1st century AD that a young astronomer called Anaxagoras predicted the meteorite’s fall to Earth, which has puzzled historians because such events are essentially random occurrences.

After studying what was said about Anaxagoras, Graham concludes that he should be recognised as “the star of early Greek astronomy”.

The study has been published in the Journal of Cosmology. (ANI)

Filed under: Science and Technology

will not be displayed