by VM44 14 Replies latest watchtower bible
Does anyone know the source of the astronomical data that Ptolemy used in his book The Alamagest?
The astronomical observations would have been time indexed using the year and day of the currently ruling king of Babylon.
This becomes important is when one computes time differences between observations, particularly if the observations spanned the reigns of two different kings!
Does anyone know the source of the astronomical data that Ptolemy used in his book The Alamagest?
Ptolemy built on Hipparchus' work (2nd c. BCE). In turn, Hipparchus was very familiar with the Babylonian archive of observational astronomy going back to the 8th c. BCE as well as their more recent mathematical astronomy.
This I found interesting.
From the wiki article on Hipparchus.
As with most of his work, Hipparchus' star catalog was adopted and perhaps expanded by Ptolemy. Delambre, in 1817, cast doubt on Ptolemy's work. It was disputed whether the star catalog in the Almagest is due to Hipparchus, but 1976–2002 statistical and spatial analyses (by R. R. Newton, Dennis Rawlins, Gerd Grasshoff, Keith Pickering and Dennis Duke) have shown conclusively that the Almagest star catalog is almost entirely Hipparchan. Ptolemy has even (since Brahe, 1598) been accused by astronomers of fraud for stating (Syntaxis, book 7, chapter 4) that he observed all 1025 stars: for almost every star he used Hipparchus' data and precessed it to his own epoch 2? centuries later by adding 2°40' to the longitude, using an erroneously small precession constant of 1° per century.
You might also like to peruse this: "Ptolemy's Use Of His Predecessors' Data" - particularly p. 236f.
The following is from Historical Eclipses and Earth’s Rotation, F. Richard Stephenson, pages 93-97
More celestial observations are preserved from Babylon than from any other contemporary civilisation. Yet until about a century ago, when large numbers of clay tablets devoted to astronomy began to be unearthed at the site of Babylon, little was known about the achievements of the skywatchers of this once great city. What could be established was mainly based on ancient Greek texts and the Old Testament. Both the Prophet Isaiah (e.g. 47:13) and the ancient Greek writer Strabo (Geography, XVI, 1.6) stress the Babylonian preoccupation with astrology. ... The ancient Greek historian Diodorus Siculus (Library of History, II, 9) implies that the lofty ziggurat - built during the reign of Nebuchadrezzar II (604-563 BC) was used as an observatory. ...
Among writers of the ancient Greek and Roman world whose works are still extant, only the great Alexandrian astronomer Claudius Ptolemy (c. AD 150) hints at the true scale on which celestial observation was practised at Babylon. In his Mathematike Syntaxis (Mathematical Systematic Treatise) - which later became known as the Almagest - Ptolemy specifically mentions sets of Babylonian eclipse observations to which he had access. ...
It is regrettable that Ptolemy actually cites no more than ten Babylonian records of lunar eclipses from the apparently large number available to him. Furthermore, no observations of solar eclipses from Babylon are preserved in the Almagest, although there are a few references to other celestial phenomena reported from this site, such as conjunctions of planets with stars. These various observations range in date from 721 to 229 BC, lunar eclipses covering the period from 721 to 382 BC.
The discovery of vast numbers of astronomical cuneiform texts at the site of Babylon during the 1870s and 1880s was eventually to revolutionise knowledge of Babylonian astronomy. These texts, which are in the form of inscribed clay tablets, range in date from about 730 BC to AD 75. Many of the eclipse records which they contain have proved so important in studies of the Earth's past rotation. ... In particular, the earlier observations must have formed the ultimate source of the material used by Hipparchus and Ptolemy. Despite the existence of this huge archive, the ten Babylonian lunar eclipse records cited in the Almagest form an interesting set of data and deserve to be analysed in their own right. ... It should be stressed that [the Assyrian cuneiform tablets of the eighth and seventh centuries BC] are mainly in the form of astrological texts and - unlike the Babylonian material - contain little quantitative information. 4.2 The Babylonian lunar eclipse records in the Almagest The very earliest astronomical records quoted in the Almagest are exclusively of Babylonian origin. ... Ptolemy evidently did not have access to material much older than 721 BC - the earliest Babylonian eclipse record which he discusses. He states (III, 7) that beginning with the reign of King Nabonassar (correct name: Nabu-nasir) of Babylon (747-733 BC) 'the ancient observations are, on the whole, preserved down to our own time'. This is apparently why Ptolemy chose the era of Nabonassar (747 BC) for numbering years. ... It is a fact that Babylonian history and chronology are extremely weak in the two centuries immediately prior to Nabonassar's reign. Even the names of several kings who ruled during this interval are unknown (cf. Oates, 1979, p.201). However, beginning with Nabonassar, Babylonian chronology is securely established.
It seems very likely that Ptolemy did not compile the list of Babylonian observations himself. The evidence points instead to Ptolemy's great predecessor Hipparchus of Rhodes (c. 150 BC). As noted above, Ptolemy specifically mentions a series of eclipse observations which had been 'brought over from Babylon' and investigated by Hipparchus. Toomer (1988) is of the opinion that the entire Babylonian record available to Ptolemy was compiled by Hipparchus, further suggesting that Hipparchus 'arranged them in a form suitable for use by Greek astronomers'. It is clear from reading the accounts of individual eclipses quoted by Ptolemy that he did not receive them at first hand. Sadly, apart from the material preserved in the Almagest, all trace of Hipparchus' compilation has long been lost.
No ancient manuscripts of the Almagest now exist; the earliest copies date from the ninth century AD (Toomer, 1984, pp. 2-4). However, as Toomer points out, there is in general very close accord between the text of individual manuscripts.
For the very earliest eclipse observations (721 and 720 BC) which he cites, Ptolemy numbers the year from the accession of Mardokempad (Marduk-apla-iddin), who was ruler of Babylon at the time. However, all later years are counted from the era of Nabonassar. Although the eclipse dates would originally be expressed in terms of the Babylonian luni-solar calendar, Ptolemy invariably specifies the month in terms of the Egyptian calendar. Numbering days from a fixed epoch was considerably simplified on this latter system. Each Egyptian year contained 12 equal months of 30 days followed by 5 epagomenal ('additional') days. This fixed year of 365 days was not adjusted to the solar year by intercalation so that the first day of the year gradually retrograded through the seasons, making a complete circuit in 1460 years (the Sothic cycle). ...
In quoting days of the month for lunar eclipses, Ptolemy was in the habit of using double dates - e.g. Thoth 18/19. This is because although the civil day began at sunset in Babylon, according to Egyptian convention it commenced at the following sunrise (Toomer, 1984, p. 12). ...
Comparison with the many lunar records found on the astronomical tablets recovered from Babylon makes it clear that the eclipse times quoted by Ptolemy are not in original form (i.e. using time-degrees) but have been modified to correspond to the Greek method (equinoctial or seasonal hours). Presumably Hipparchus was responsible for these reductions. It is a pity that the original measurements are not preserved; it is likely that some loss of accuracy would occur when the times were reduced to the Greek system. However, no attempt at restoration is possible. Only in a single case (523 BC) is there a parallel inscription on an extant cuneiform tablet, and even this is problematical.
D. MASON: "Only in a single case (523 BC) is there a parallel inscription on an extant cuneiform tablet, and even this is problematical." 523 BC is the revised date for the 7th year of Ptolemy. The "extant" COPY that matches this single parallel is the SK400 which was a "copy" created during the Seleucid Period. It is NOT a extant contemporary document from that year. Thus like the VAT4956, which is also a "copy" from the Seleucid Era, some 200+ years after the fact, the historical information cannot be trusted as the WTS has pointed out. Now the "problem" here is that Ptolemy and the SK400 both record an eclipse on Tammuz 14 as beginning "one hour before midnight", that is, around 11 p.m. give or take 4 minutes. The SK400 records this eclipse beginning specifically at 3:20 "after night". That is, 3 hours 20 minutes after "night" begins, which is a Babylonian division of the night, 32 minutes after sunset. That is, sunset occurs on this date at 7:09 p.m. Add 32 minutes and you get 7:41 p.m. as the "beginning of night." Add 3:20 to this and you get 10:61, which is 11:01, and thus 1 hour after midnight within 4 minutes, the smallest observed rounded interval used by the Babylonians. Of course, you have two documents now that coordinate earth time with lunar time. Thus you can determine by this single reference within a minute precisely how to coordinate the Earth's rotational position and thus "speed of deceleration" by this reference. But the popular astronomers prefer another reference for determining this, a single solar eclipse reference in the 4th century BC as I recall. When making their calculations adjusted by a "delta-T" factor, the eclipse in 523 BCE, which by two texts time the eclipse precisely at "one hour before midnight" we find it is dated from Babylon 3 minutes after 10 p.m., thus representing a 57-minute discrepancy. So, yes, this is "problematic." That doesn't even address the second eclipse reference in the SK400 which is timed to 5 hours before morning which creates a 2:46 interval of time between the two eclipses. That is, it is represented as occurring at 1:47, thus: The eclipse is dated to Tebet 14 (6 months after Tammuz 14 eclipse), 5 hours before morning. Sunrise was at 7:19 a.m., which is 6:79. "Morning" begins 32 minutes before sunrise and thus at 6:47 a.m. (6:79 - 32 = 6:47). We then subtract 5 hours from this to get 1:47 a.m. (6:47 - 5:00 = 1:47). One hour before midnight would create an interval between these two eclipses of 2:47. But because the SK400 is more specific about the precise time based on the time of sunset at 7:09, we subtract 1 minute to get 2:46. That is, the interval between 11:01 p.m. and 1:47 a.m. is 2:46. Or in other words, 60 minutes added to 1:47 is 2:47, 59 minutes added to 1:47 is 2:26. The PROBLEM is, though, the interval between the eclipses in 523 BCE is 2 hours greater at 4:46. So yes, there is a "problem" with this incredible parallel reference. I've done research at several universities of the astronomical texts and basically once these astronomical texts were found, there was some interest in it becoming an academic specialty relating to ASTROCHRONOLOGY. But they began to find so many contradictions and problems that that idea just fizzled out and there is nothing there but some specialized inquiries. So that is the state of things. Of course, we might wonder why is that? Why are the contemporary Babylonian astronomical texts missing? Why are a couple of "copies" so critical to Babylonian dating? The two "extant" copies being the SK4090 and the VAT4956, both mentioned by Robert Newton who otherwise considers Ptolemy a complete historical fraud. The answer to that is that the popular history was revised last by Xenophon who used astronomical references to set the new Babylonian timeline. Then later the extant contemporary records were either destroyed or revised, adding the new kinglist to the revised documents. Original astronomical texts seldom were concerned about who was ruling at the time. But revisionists would be. So when you see a king connected with an astronomical text, it is a dead giveaway it is part of a revisionist scheme. Having noted that, therefore, any astronomical texts that reflect the revised dating from Xenophon we know for a fact is a fake astronomical text. Xenophon added a net 57 fake years to the Greek timeline. This pushed Babylonian dates at the time of Nebuchadnezzar back 57 years. Thus the VAT4956 reflects the 57-year discrepancy by inserting dates from the original year 37 of Nebuchadnezzar in 511 BCE (in lines 3 and 14) along with many references to the revised date of 568 BCE. So "diaries" were actually created as "safety texts" to record from the original astronomical texts that were fated to destruction in the context of the revised, popular chronology. So Ptolemy's canon had no option but to copy from these revised astronomical texts that had already redated the kings from the Neo-Babylonian Period. That's why Ptolemy's canon doesn't even get on the table as a reference, other than as a background reference for how extensively the astronomical texts were revised. What is wonderful, though, is that the parallel reference found for the Tammuz 14 eclipse dated to "one hour before midnight" gives us a critical eclipse reference for the original chronology. That is, we can use that single eclipse reference to correct all eclipse times when it is dated to the original event, which was not 523 BCE, year 7 of Kambyses, but "year 7" of Nebuchadnezzar in 541 BCE. That is, the eclipse interval of 2:46 is a non-match to 523 BCE, which is an interval of 4:46. But 18 years earlier is a precise match for that that interval in 541 BCE. If we presume a transfer of that eclipse time and dating, we get year 7 of Nebuchadnezzar in 541 BCE, which matches the VAT4956's dating of year 37 in 511 BCE. So it's a done deal at this point what is going on. The eclipse and astronomical information doesn't match well because of the revisions and because of an attempt to not only change the historical information but the lunar eclipse times. So a critical discussion of Ptolemy in the absence of the Biblical timeline which dates the 1st of Cyrus to 455 BCE and year 23 to 525 BCE is basically just irrelevant to any true dating for the period. So academically, Ptolemy would be considered to be spurious and thus unrelated to the Biblical timeline. So this is handled analytically, which means you simply observe what dating Ptolemy is representing and compare that to the VAT4956 and SK400 and the Bible's timeline, then make up your own mind which or if either are reliable. The important thing is to observe that the Bible's dating for the Neo-Babylonian Period is some 26 years longer than that represented by Ptolemy which is a foundation to the popular timeline. Of note, Josephus and the Bible both introduce 70 years of exile for the last deportees, year 23 of Nebuchadnezzar II. That means from the fall of Babylon to the 1st of Cyrus is 74-75 years. Popular chronology dating the fall of Jerusalem in 587 BCE and the return in 537 BCE is a 50-year interval. So to begin a discussion of astrochronology in the context of Bible chronology, you first have to recognize there is never going to be any compatibility. One represents the revised timeline and the other the original. Fortunately, the VAT4956 and the SK400 can be used to establish the absolute original rule of Nebuchadnezzar II beginning in 547 BCE which allows us the critical comparison to Biblical chronology for year 23 of Nebuchadnezzar based on 455 BCE for the 1st of Cyrus, 70 years later. That comparison shows 100% compatibility. That is, the SK400 dating year 7 to 541 BCE agrees with the VAT4956 dating year 37 to 511 BCE, which agrees with dating year 23 to 525 BCE, exactly 70 years earlier than 455 BCE, the true date for the 1st of Cyrus. Your welcome. LS
Ooops! Sorry about the formatting! I have no idea what is going on. I think I'm being sabbotaged by my opposers! ??? LS
D. MASON: "Only in a single case (523 BC) is there a parallel inscription on an extant cuneiform tablet, and even this is problematical." 523 BC is the revised date for the 7th year of Ptolemy. The "extant" COPY that matches this single parallel is the SK400 which was a "copy" created during the Seleucid Period. It is NOT a extant contemporary document from that year. Thus like the VAT4956, which is also a "copy" from the Seleucid Era, some 200+ years after the fact, the historical information cannot be trusted as the WTS has pointed out.
Now the "problem" here is that Ptolemy and the SK400 both record an eclipse on Tammuz 14 as beginning "one hour before midnight", that is, around 11 p.m. give or take 4 minutes. The SK400 records this eclipse beginning specifically at 3:20 "after night". That is, 3 hours 20 minutes after "night" begins, which is a Babylonian division of the night, 32 minutes after sunset. That is, sunset occurs on this date at 7:09 p.m. Add 32 minutes and you get 7:41 p.m. as the "beginning of night." Add 3:20 to this and you get 10:61, which is 11:01, and thus 1 hour after midnight within 4 minutes, the smallest observed rounded interval used by the Babylonians. Of course, you have two documents now that coordinate earth time with lunar time. Thus you can determine by this single reference within a minute precisely how to coordinate the Earth's rotational position and thus "speed of deceleration" by this reference.
But the popular astronomers prefer another reference for determining this, a single solar eclipse reference in the 4th century BC as I recall. When making their calculations adjusted by a "delta-T" factor, the eclipse in 523 BCE, which by two texts time the eclipse precisely at "one hour before midnight" we find it is dated from Babylon 3 minutes after 10 p.m., thus representing a 57-minute discrepancy. So, yes, this is "problematic." That doesn't even address the second eclipse reference in the SK400 which is timed to 5 hours before morning which creates a 2:46 interval of time between the two eclipses. That is, it is represented as occurring at 1:47, thus: The eclipse is dated to Tebet 14 (6 months after Tammuz 14 eclipse), 5 hours before morning. Sunrise was at 7:19 a.m., which is 6:79. "Morning" begins 32 minutes before sunrise and thus at 6:47 a.m. (6:79 - 32 = 6:47). We then subtract 5 hours from this to get 1:47 a.m. (6:47 - 5:00 = 1:47). One hour before midnight would create an interval between these two eclipses of 2:47. But because the SK400 is more specific about the precise time based on the time of sunset at 7:09, we subtract 1 minute to get 2:46. That is, the interval between 11:01 p.m. and 1:47 a.m. is 2:46. Or in other words, 60 minutes added to 1:47 is 2:47, 59 minutes added to 1:47 is 2:26. The PROBLEM is, though, the interval between the eclipses in 523 BCE is 2 hours greater at 4:46. So yes, there is a "problem" with this incredible parallel reference.
I've done research at several universities of the astronomical texts and basically once these astronomical texts were found, there was some interest in it becoming an academic specialty relating to ASTROCHRONOLOGY. But they began to find so many contradictions and problems that that idea just fizzled out and there is nothing there but some specialized inquiries. So that is the state of things. Of course, we might wonder why is that? Why are the contemporary Babylonian astronomical texts missing? Why are a couple of "copies" so critical to Babylonian dating? The two "extant" copies being the SK4090 and the VAT4956, both mentioned by Robert Newton who otherwise considers Ptolemy a complete historical fraud. The answer to that is that the popular history was revised last by Xenophon who used astronomical references to set the new Babylonian timeline. Then later the extant contemporary records were either destroyed or revised, adding the new kinglist to the revised documents. Original astronomical texts seldom were concerned about who was ruling at the time. But revisionists would be. So when you see a king connected with an astronomical text, it is a dead giveaway it is part of a revisionist scheme.
Having noted that, therefore, any astronomical texts that reflect the revised dating from Xenophon we know for a fact is a fake astronomical text. Xenophon added a net 57 fake years to the Greek timeline. This pushed Babylonian dates at the time of Nebuchadnezzar back 57 years. Thus the VAT4956 reflects the 57-year discrepancy by inserting dates from the original year 37 of Nebuchadnezzar in 511 BCE (in lines 3 and 14) along with many references to the revised date of 568 BCE. So "diaries" were actually created as "safety texts" to record from the original astronomical texts that were fated to destruction in the context of the revised, popular chronology. So Ptolemy's canon had no option but to copy from these revised astronomical texts that had already redated the kings from the Neo-Babylonian Period.
That's why Ptolemy's canon doesn't even get on the table as a reference, other than as a background reference for how extensively the astronomical texts were revised. What is wonderful, though, is that the parallel reference found for the Tammuz 14 eclipse dated to "one hour before midnight" gives us a critical eclipse reference for the original chronology. That is, we can use that single eclipse reference to correct all eclipse times when it is dated to the original event, which was not 523 BCE, year 7 of Kambyses, but "year 7" of Nebuchadnezzar in 541 BCE. That is, the eclipse interval of 2:46 is a non-match to 523 BCE, which is an interval of 4:46. But 18 years earlier is a precise match for that that interval in 541 BCE. If we presume a transfer of that eclipse time and dating, we get year 7 of Nebuchadnezzar in 541 BCE, which matches the VAT4956's dating of year 37 in 511 BCE. So it's a done deal at this point what is going on. The eclipse and astronomical information doesn't match well because of the revisions and because of an attempt to not only change the historical information but the lunar eclipse times.
So a critical discussion of Ptolemy in the absence of the Biblical timeline which dates the 1st of Cyrus to 455 BCE and year 23 to 525 BCE is basically just irrelevant to any true dating for the period. So academically, Ptolemy would be considered to be spurious and thus unrelated to the Biblical timeline. So this is handled analytically, which means you simply observe what dating Ptolemy is representing and compare that to the VAT4956 and SK400 and the Bible's timeline, then make up your own mind which or if either are reliable. The important thing is to observe that the Bible's dating for the Neo-Babylonian Period is some 26 years longer than that represented by Ptolemy which is a foundation to the popular timeline. Of note, Josephus and the Bible both introduce 70 years of exile for the last deportees, year 23 of Nebuchadnezzar II. That means from the fall of Babylon to the 1st of Cyrus is 74-75 years. Popular chronology dating the fall of Jerusalem in 587 BCE and the return in 537 BCE is a 50-year interval.
So to begin a discussion of astrochronology in the context of Bible chronology, you first have to recognize there is never going to be any compatibility. One represents the revised timeline and the other the original. Fortunately, the VAT4956 and the SK400 can be used to establish the absolute original rule of Nebuchadnezzar II beginning in 547 BCE which allows us the critical comparison to Biblical chronology for year 23 of Nebuchadnezzar based on 455 BCE for the 1st of Cyrus, 70 years later. That comparison shows 100% compatibility. That is, the SK400 dating year 7 to 541 BCE agrees with the VAT4956 dating year 37 to 511 BCE, which agrees with dating year 23 to 525 BCE, exactly 70 years earlier than 455 BCE, the true date for the 1st of Cyrus.
Your welcome.
LS
Larry,
I'm glad you finally worked out the problems with your formatting.
When you look carefully at my post, you will see that they were not my words, but that I was providing an answer to the original question from an objective source.
So that I do not have to wade through all the detail, could you tell me very simply which date you start from and where you get that originating date from.
Thanks,
Doug
