Posted on 05/20/2012 12:29:35 PM PDT by SunkenCiv
The study of the "Demon star", Algol, made by a research group of the University of Helsinki, Finland, has received both scientific and public attention. The period of the brightness variation of this eclipsing binary star has been connected to good prognoses three millennia ago. This result has raised a lot of discussion and the news has spread widely in the Internet.
The Egyptian papyrus Cairo 86637 calendar is probably the oldest preserved historical document of bare eye observations of a variable star. Each day of one Egyptian year was divided into three parts in this calendar. A good or a bad prognosis was assigned for these parts of a day...
A modern period analysis revealed that two statistically significant periods of 29.6 and 2.850 days have been recorded into the good prognoses. The former is clearly the period of the Moon. The second period differs slightly from the period Algol. In this eclipsing binary, the dimmer star partially covers the brighter star with a period of 2.867 days...
The ancient Egyptians have made accurate measurements that provide useful constraints for modern astronomers.
(Excerpt) Read more at phys.org ...
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I believe the Greeks used to incorporate the dimming cycle of Algol into their story of Perseus. (when he stole the shared eye of the 3 fates)
Thanks cc.
2.850 days Vs 2.867 days. Is this an indication of a slightly inaccurate observation 4500 years ago, or an indication of a longer period today?
The latter.
Possibly relevant sidebar:
In the shadow of the Moon
New Scientist | 30 January 1999 | editors
Posted on 08/31/2004 8:42:25 AM PDT by SunkenCiv
http://www.freerepublic.com/focus/chat/1203912/posts
Thought so. Thanks.
“good prognosis.”
An event you can watch even in smaller cities. You don’t need any special equipment, just your eyes and an idea of where Perseus is in the sky.
Ancient Egyptians were amazing architects, astronomers, physicians and artists.
I WONDER what caused their sophisticated culture to deteriorate to that of a 7th century cesspool...Hmmmm...I WONDER.
The ancients considered Caput Algol a very evil star. Dishonor, disaster, horrible death, etc.
Astrologers could confirm that Algol is prominent in the horoscope of the Poodle. IIRC, he had Venus in the same degree.
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