The Lunar Date of Ramesses II
Open accessAbstract
Due largely to the efforts of R. A. Parker, the various calendars used in Egypt are now fairly well understood. Dates which the Egyptians expressed in both their civil and lunar calendars can sometimes be determined exactly, and the study of such dates has been extremely important in efforts to establish an accurate Egyptian chronology. However, the successful use of this method obviously depends on one's ability to reconstruct accurately the astronomical and observational conditions on which the lunar calendar was based. The author re-examined the methods used to calculate lunar dates and have suggested some ways in which those methods could be made more accurate. The revised procedures were applied to the lunar dates of Thutmose III, and those dates would be valuable in fixing the chronology of the early Eighteenth Dynasty. In a similar way, there is a lunar date associated with the reign of Ramesses II, and that date is important in establishing an absolute chronology for the early Nineteenth Dynasty. The purpose of this article is to describe briefly the results of applying the revised lunar calculation procedures to the lunar date of Ramesses II.
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TL;DR
Casperson recalculates lunar visibility for the date II prt 27 of Ramesses II’s fifty-second year, recorded as *psdntyw* (crescent not visible before sunrise), to test competing accession years. The results favor 1279 B.C. as the most plausible accession date, while 1301, 1290, and 1276 B.C. are excluded or in poor agreement and 1304 B.C. cannot easily be harmonized.
Key findings
- For a 1304 B.C. accession, the new moon fell on the afternoon of 26 December 1253 B.C., Egyptian date II prt 28; sunrise visibility was 19, too near the horizon to be visible, but one day earlier visibility was 146, meaning the crescent could plainly be seen. This is inconsistent unless the observer missed the crescent, and a lunar month of twenty-eight days is impossible; the observers would also have had to miss a marginally visible crescent (visibility 104) the previous month on I prt 28.
- A 1301 B.C. accession can safely be excluded: observers would have had to claim to see the crescent on II prt 26 when it was already marginally invisible (visibility 99) the day before, and an invisible crescent would have to have been “seen” on I prt 26 to avoid a lunar month of thirty-one days.
- A 1290 B.C. accession is in poor agreement because observers would have had to “see” an invisible crescent on II prt 26; a 1276 B.C. accession can probably be excluded because observers would have had to “see” invisible crescents for two months in succession.
- A 1279 B.C. accession is almost consistent: observers would have had to miss a marginally visible crescent (visibility 107) on II prt 27, which is not an unlikely error. The author prefers 1279 B.C. over 1304 B.C. because the theoretical crescent visibility was only marginal, and with slightly more conservative estimates the moon may actually have been invisible on the morning of II prt 27.
Methods
- The study applies revised lunar calculation procedures to the lunar date II prt 27 of Ramesses II’s fifty-second year, recorded as *psdntyw*, and recalculates observational conditions for the five most likely accession dates identified by Parker in 1957: 1304, 1301, 1290, 1279, and 1276 B.C.
- It assumes the king’s astronomers had the observational capabilities of an idealized Jerusalem observer, and Table 1 lists new moon data for an observation site at Heliopolis and Jerusalem visibility coefficients.
- The table gives local sunrise time and lunar visibility for three days near conjunction: the zero column is the date of conjunction, minus one is one day before, and minus two is two days before; visibility numbers represent one hundred times the ratio of lunar height at sunrise to the minimum height for visibility.
Limitations
- Stated: the author notes it is regrettable that there is not more direct evidence on the observational abilities of the Egyptians, and suggests there would probably be considerable value in modern observations of the lunar crescent at Memphis, Heliopolis, and Thebes.
- Stated: the calculations assume the king’s astronomers had the observational capabilities of an idealized Jerusalem observer.
- Evident: the conclusions depend on visibility coefficients and on the assumption that missing a visible crescent is more likely than “seeing” an invisible one; the paper also notes that none of Parker’s dates yielded exact agreement with his astronomical calculations.
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- Findingown data§ The lunar date of Ramesses II The lunar date of Ramesses II
From the last section of Table 1, the observers would have to have seen invisible crescents for two months in succession.
“From the last section of the table one finds that the observers would have to have “seen” invisible crescents for two months in succession.”
Quote in the paperSubstantial claim - Findingown data§ The lunar date of Ramesses II The lunar date of Ramesses II
From the eighteenth line of Table 1, the observers would have to have missed a marginally visible crescent (visibility 107) on II prt 27.
“From the eighteenth line of the table one finds that the observers would have to have missed a marginally visible crescent (visibility 107) on II prt 27.”
Quote in the paperSubstantial claim - Findingown data§ The lunar date of Ramesses II The lunar date of Ramesses II
One day earlier than 26 December 1253 B.C., the visibility of 146 means that the crescent could in principle be plainly seen.
“One day earlier, however, the visibility of 146 means that the crescent could (in principle) be plainly seen.”
Quote in the paperSubstantial claim - Findingown data§ The lunar date of Ramesses II The lunar date of Ramesses II
From the thirteenth line of Table 1, the observers would have to have seen an invisible crescent on II prt 26.
“From the thirteenth line of the table one finds that the observers would have to have “seen” an invisible crescent on II prt 26.”
Quote in the paperSubstantial claim - Findingown data§ The lunar date of Ramesses II The lunar date of Ramesses II
From the eighth line of Table 1, the observers would have to have claimed to see the crescent on II prt 26 when it was already marginally invisible (visibility 99) the day before.
“From the eighth line of the table one finds that a 1301 B.C. accession date can safely be excluded, since the observers would have to have claimed to see the crescent on II prt 26 when it was already marginally invisible (visibility 99) the day before.”
Quote in the paperSubstantial claim
- Findingown data§ The lunar date of Ramesses II The lunar date of Ramesses II
At sunrise on 26 December 1253 B.C., the visibility of 19 means that the lunar crescent was too near the horizon to be visible.
“At sunrise on that day, the visibility of 19 means that the lunar crescent was too near the horizon to be visible.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
With slightly more conservative estimates of Egyptian observational capabilities, the moon may actually have been invisible on the morning of II prt 27.
“In fact, with slightly more conservative estimates of Egyptian observational capabilities, one finds that the moon may actually have been invisible on the morning of II prt 27.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
A 1276 B.C. accession date can probably be excluded.
“Thus, a 1276 B.C. accession date can probably be excluded.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
The invisible crescent would have to have been seen on I prt 26 to avoid a lunar month of thirty-one days.
“Furthermore, the invisible crescent would have to have been “seen” on I prt 26 to avoid a lunar month of thirty-one days.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
A 1279 B.C. accession date is almost consistent with the text.
“This is not an unlikely kind of error, and thus a 1279 B.C. accession date is almost consistent with the text.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
The 1290 B.C. accession date is in poor agreement with the text.
“Thus, the 1290 B.C. accession date is in poor agreement with the text.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
The lunar month should have begun on II prt 28, the first day of crescent invisibility.
“Thus, the lunar month should have begun on II prt 28, the first day of crescent invisibility.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
Of the candidate dates, the 1279 B.C. date is more attractive, since the theoretical crescent visibility was only marginal for the corresponding observation.
“Of these, the 1279 B.C. date is more attractive, since the theoretical crescent visibility was only marginal for the corresponding observation.”
Quote in the paperSubstantial claim- Rests on an assumption: It is more likely for an observer to miss a visible crescent than to see an invisible one.
- Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
Since a lunar month of twenty-eight days is not possible, the observers would have to have missed the marginally visible crescent (visibility 104) the previous month on I prt 28.
“Also, since a lunar month of twenty-eight days is not possible, the observers would have to have missed the marginally visible crescent (visibility 104) the previous month on I prt 28.”
Quote in the paperSubstantial claim- Rests on an assumption: A lunar month of twenty-eight days is not possible.
- Interpretationnone given§ The lunar date of Ramesses II The lunar date of Ramesses II
Missing a marginally visible crescent is not an unlikely kind of error.
“This is not an unlikely kind of error, and thus a 1279 B.C. accession date is almost consistent with the text.”
Quote in the paperNot a substantial claim - Interpretationown data§ The lunar date of Ramesses II The lunar date of Ramesses II
A 1301 B.C. accession date can safely be excluded.
“From the eighth line of the table one finds that a 1301 B.C. accession date can safely be excluded, since the observers would have to have claimed to see the crescent on II prt 26 when it was already marginally invisible (visibility 99) the day before.”
Quote in the paperSubstantial claim - Interpretationreasoning§ The lunar date of Ramesses II The lunar date of Ramesses II
An accession year of 1304 B.C. cannot easily be harmonized with the text.
“Thus an accession year of 1304 B.C. cannot easily be harmonized with the text.”
Quote in the paperSubstantial claim
- May combine two claims. 2
- Classified as probably not a substantial claim. 1
May combine two claims.
Findingown data§ The lunar date of Ramesses II The lunar date of Ramesses IIFrom the third row of Table 1, there was a new moon on the afternoon of 26 December 1253 B.C., and in the Egyptian calendar this was the twenty-eighth day of the sixth month II prt.
“From the third row of the table one finds that there was a new moon on the afternoon of 26 December 1253 B.C., and in the Egyptian calendar this was the twenty-eighth day of the sixth month II prt.”
Quote in the paperSubstantial claimClassified as probably not a substantial claim. May combine two claims.
Premisecitation§ The lunar date of Ramesses II The lunar date of Ramesses IIThe author has recently re-examined the methods used to calculate lunar dates and has suggested some ways in which those methods could be made more accurate.
“I have recently re-examined the methods used to calculate lunar dates and have suggested some ways in which those methods could be made more accurate.2”
Quote in the paperSubstantial claim0 of 1 sources checked- cites [2]
Couldn’t be matched to a paper in Crossref, so it can’t be checked.
The authors state this as an assumption.
The king's astronomers had the observational capabilities of an idealized Jerusalem observer.
“For consistency, I have assumed as before that the king's astronomers had the observational capabilities of an idealized Jerusalem observer.”
The paper relies on this without support.
The lunar date II prt 27 of the fifty-second year of Ramesses II is recorded as psdntyw, i.e., the lunar crescent was not visible before sunrise.
“The date of interest is II prt 27 of the fifty-second year of Ramesses II, and that date is recorded as being pidntyw, i.e., the lunar crescent was not visible before sunrise.”
The paper relies on this without support.
It is more likely for an observer to miss a visible crescent than to see an invisible one.
“If it is more likely for an observer to miss a visible crescent than to “see” an invisible one, then one should prefer either 1304 B.C. or 1279 B.C.”
The paper relies on this without support.
A lunar month of twenty-eight days is not possible.
“Also, since a lunar month of twenty-eight days is not possible, the observers would have to have missed the marginally visible crescent (visibility 104) the previous month on I prt 28.”
Cites
The publisher hasn’t deposited this paper’s reference list.
Research works printed but not linked: 9
- Rowton, "The Background of the Treaty be- tween Ramesses II and Hattusilis III," JCS 13 (1959): 1-11; idem, "Comparative Chronology at the Time of Dynasty XIX," JNES 19 (1960): 15-22; idem, "The Material from Western Asia and the Chronology of the Nineteenth Dynasty," JNES 25 (1966): 240-58.
- Idem, "New Light on the Asiatic Campaigning of Horemheb," BASOR 211 (1973): 36-49.
- K. A. Kitchen, "On the Chronology and His- tory of the New Kingdom," Chronique d'Egypte 40 (1965): 310-22.
- E. F. Wenie and C. C. Van Siclen III, "A Chronology of the New Kingdom," in Janet H. Johnson and Edward F. Wente, eds., Studies in Honor of George R. Hughes, SAOC 39 (Chicago, 1976), pp. 217-66.
- R. Krauss, Das Ende der Amarnazeit, Hil- desheimer agyptologische Beitrage 7 (Hildesheim, 1978), pt. 2; idem, Sothis-und Monddaten, Hil- desheimer agyptologishche Beitrige 20 (Hildesheim, 1985), pp. 119-44.
- Hornung, "Chronologie in Bewegung," in M. G6rg and E. Pusch, eds., Festschrift Elmar Edel (Bamberg, 1979), pp. 247-52.
- Kitchen, review of Studies in Honor of George R. Hughes in Serapis 4 (1977-78), pp. 65-80.
- Parker, "Some Reflections on the Lunar Dates of Thutmose III and Ramesses II," in W. K. Simpson and W. M. Davis, eds., Studies in Ancient Egypt, the Aegean, and the Sudan: Essays in Honor of Dows Dunham (Boston, 1981), pp. 146-48.
- Excavations at the site of the ancient city of Emar imply that the destruction of that city and other associated Syro-Hittite sites occurred after 1191 B.C. In the words of Bierbrier, "Destruction of Emar," the incorporation of this new information into Egyptian chronology "casts strong doubt on the 1304 B.C. date." 21 Parker, "Lunar Dates," pp. 42-43.
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“…whether or not an astronomical date is ‘possible’, it might seem sounder to regard all the resulting solutions as equally viable; but in fact L.W.Casperson (1988) has recently argued that on purely astronomica1 grounds 1304 BC and 1279 BC are more probable dates for the accession of Ramesses…”
Background
- Authors
- Casperson, L. W.
- Affiliations
- Portland State University (US)
- Corresponding author
- Casperson, Lee W.
- Venue
- Journal of Near Eastern Studies
- Publisher
- University of Chicago Press
- Published
- 1988-07
- Volume
- 47
- Issue
- 3
- Pages
- 181-184
- ISSN
- 0022-2968 (ISSN-L)
- 1545-6978
- OpenAlex
- W2091162505
- Cited by
- 5
- References
- 0
- Citations by year
- 2020: 1 · 2014: 1
- FWCI
- 20.34
- Type
- journal article
- Language
- en
- Open access
- Locations
- Journal of Near Eastern Studies (publishedVersion)
- PDXScholar (Portland State University) (submittedVersion)
- Topics
- Social Sciences › Arts and Humanities › Archeology › Ancient Egypt and Archaeology
- Physical Sciences › Physics and Astronomy › Astronomy and Astrophysics › Historical Astronomy and Related Studies
- Social Sciences › Arts and Humanities › Archeology › Historical and Architectural Studies
- Keywords
- Ramesses II, lunar calendar, Egyptian chronology, Thutmose III, Eighteenth Dynasty, 19th Dynasty
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