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Swift
2016-Jan-29, 08:14 PM
From Laboratory Equipment magazine (http://www.laboratoryequipment.com/news/2016/01/babylonian-astronomers-used-geometry-centuries-europeans?et_cid=5083684&et_rid=54636800&type=image&et_cid=5083684&et_rid=54636800&linkid=http%3a%2f%2fwww.laboratoryequipment.com%2f news%2f2016%2f01%2fbabylonian-astronomers-used-geometry-centuries-europeans%3fet_cid%3d5083684%26et_rid%3d%%subscrib erid%%%26type%3dimage)


Jupiter was important to the Babylonians. It was identified with the city’s patron god, Marduk, and was one of the hallmark features in the night sky visible to the ancient naked eye.

For thousands of years, historians and archaeologists believed the Mesopotamian astronomers used simple arithmetic to calculate the giant planet’s travel across the sky. But a new discovery, found gathering dust in the British Museum, shows the ancients were already using geometry, many centuries before some of their European counterparts, according to a paper in Science.

Four cuneiform tablets were unearthed in the 19th century near the ruins of Babylon’s main temple. All were dated between 350 and 50 B.C., and all described geometrical equations. But they were heavily damaged, and archaeologists could make no sense of them – partly because they didn’t know what they were referring to.

But the discovery of a fifth tablet never before analyzed in the British Museum provided the context that told the whole story. Together, the “trapezoid texts” referred to the transit of Jupiter across the night sky.

“These computations anticipate the use of similar techniques by European scholars, but they were carried out at least 14 centuries earlier,” said Mathieu Ossendrijver, historian of science at Humboldt-Universitat zu Berlin, the author. “The new interpretation reveals that Babylonians astronomers also used geometrical methods.”


Link to the article in Science (http://science.sciencemag.org/content/351/6272/482)


The idea of computing a body’s displacement as an area in time-velocity space is usually traced back to 14th-century Europe. I show that in four ancient Babylonian cuneiform tablets, Jupiter’s displacement along the ecliptic is computed as the area of a trapezoidal figure obtained by drawing its daily displacement against time. This interpretation is prompted by a newly discovered tablet on which the same computation is presented in an equivalent arithmetical formulation. The tablets date from 350 to 50 BCE. The trapezoid procedures offer the first evidence for the use of geometrical methods in Babylonian mathematical astronomy, which was thus far viewed as operating exclusively with arithmetical concepts.

Cougar
2016-Jan-29, 08:57 PM
From another article...


"They're in a way like modern scientists and in a way they're very different," says Jones. "But they're still coming up with things that we can recognize as being like what we value as mathematics and science."

Yes, different in the astrology and the Jupiter as god part.

Not to diminish any of their early discovery and use of mathematics and geometry.

tusenfem
2016-Jan-30, 06:10 PM
A very interesting paper.
When I see what my Utrecht student-colleague is doing with those cuniform texts, I regret not finishing that course.
Ah well, you can't do everything :-)
Just wondering what other interesting stuff there is in untranslated tablets.

Cougar
2016-Jan-30, 07:15 PM
Jupiter’s displacement along the ecliptic is computed as the area of a trapezoidal figure obtained by drawing its daily displacement against time.

I don't follow. :confused-default: I'm looking at Jupiter's path from 2014-2018 (http://www.nakedeyeplanets.com/jupiter.htm) as an example. I guess I'm not understanding what they're measuring. Displacement along the ecliptic?

ngc3314
2016-Jan-30, 07:41 PM
AIUI, the used (for example) night-to-night angular displacement as a measure if what we call angular velocity, and get its total movement from a starting point by what amounts to integrating that by a linear approximation.(What I don't get from those news bits is why that was preferable to just measuring from a starting point, except that this might give a more explicit estimate of what happened at unobservable times, which can matter for astrological calculations).

publiusr
2016-Jan-30, 08:08 PM
I heard it first on Coast-to-Coast AM.

When I heard it elsewhere, I knew the news was real.

slang
2016-Jan-31, 02:07 AM
A very interesting paper.
When I see what my Utrecht student-colleague is doing with those cuniform texts, I regret not finishing that course.

It IS funny that when the newspapers here report about it, they start "A Dutch scientist discovered that...". :)