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Siriusly Red

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#1 Otto Piechowski

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Posted 09 November 2012 - 12:11 AM

I was reading Ptolemy's Almagest this evening. For those of you not familiar with this text, it was written around A.D. 150.

At the beginning of Book 8 he continues describing the brighter stars in the constellations. When he comes to Canis Major, he describes Sirius by using a Greek word (pronounced hoo-poh-key-ros).

Sometime later, this original Greek text was translated into Arabic. Later the Arabic was translated into Latin. And finally, under the influence of the Latin version, Ptolemy's description of Sirius was translated into English as, "The brightest and red star in the face called the Dog."

Now to backtrack just a bit. The Latin version is different from this English rendition in two regards. First, the word used is subruffa which at best means something like straw-colored. Second, the use of subruffa appears at the end of the description of Sirius; not in the middle; i.e. & [et] est subruffa.

Very scholarly examinations of these texts have determined that Ptolemy did not mean to say, nor did he in fact say, that Sirius appeared red.

A problem I see with this nearly definitive scholarly opinion is that in the Latin text the word used to describe Sirius as red (i.e. subruffa) is also used to describe Betelgeuse, which clearly is reddish and clearly appears different from Sirius.

Now, the use of the same word in the Latin to describe the hue of Betelgeuse and Sirius is somewhat irrelevant as we are dealing with a translation of a translation.

What might actually determine a problem with the scholarly opinion is if the Greek language text of the almagest uses this same word (i.e. hoo-poh-key-ros) to describe both Betelgeuse and Sirius. (As an aside, I do know that in another work by Ptolemy, he did use this Greek word (hoo-poh-key-ros) to describe Betelgeuse. This is relevant but is not the "smoking gun" that the use of this same Greek language word for both in the almagest would be.)

I would have done just this myself and not have even brought the issue up here, except for the fact that I have met with failure in my many attempts to download the only Greek text version of the Almagest I could find on the web. (It is found under somthing called "namas te" on the site www.wilbourhall.org in a link under Ptolemy (listed in English, and Arabic).)

Is there anyone here interested enough, totally without a life, bored to absolute tears, who would be willing to download this Greek text version and some other English translation version and see if the same Greek word is used in both the descriptions of Betelgeuse and Sirius?

Any takers?

#2 Andy Taylor

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Posted 09 November 2012 - 01:50 AM

Sorry - I'm washing my hair tonight...

#3 Qwickdraw


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Posted 09 November 2012 - 05:36 AM

Otto, they just seem to be very bog PDF's in the range of 90 meg. Try again and wait about 10 minutes for the download over cable. If you are using DSL or dial up I would not even try it

#4 dickbill


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Posted 09 November 2012 - 10:02 AM

i downloaded the first file on the top of the list.
"The complete Almagest (books 1- 13). Requires Adobe Acrobat reader version 8 or higher. (17 Mb). This copy was used by Dr. David Pingree. (Greek)"

It stopped at 37%, wait 10 minutes, then PAUSE and RESUME the download until completion.
Try again, it should work.

Once downloaded, unfortunately it's a scanned image text. It is of quite good quality for character recognition to save as a searchable 'WORD' document in greek, which you can do online using the 'save AS WORD ONLINE' with the 'optical character recognition' option.

#5 EJN



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Posted 09 November 2012 - 12:17 PM

This subject was covered in an article on this very site - see:



#6 Otto Piechowski

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Posted 09 November 2012 - 04:34 PM

Thank you EJN. That article and the subsequent discussion certainly did seem to cover the issue in great depth.


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