Sothis cycle

The constellation Sopdet with the star Sirius in hieroglyphics
Greek	Σωθις (Sothis)
	Sirius (left) and his smaller companion Sirius B (right) ; (photomontage)

Sothis cycle (also Sothis period ) is the period of about 1424 years that Sirius (the brightest star in the sky) with his heliacal (" belonging to the rising sun ") needs to achieve the 365 days used in ancient Egypt -Calendar to cycle through. This took into account the fact, which was still unknown in ancient Egypt, that the 365-day calendar year used (without leap days) as a year determining the seasons was a little too short, or vice versa, this calendar year was once a star year in around 1460 years ( sidereal Year ).

The vernal equinox runs through the 365-day calendar at the same speed and in principle in the same way as a sidereal year, assuming that the sun passes the vernal equinox every exactly 365.25 days (correct value: 365.2422 days) in 1460 years .

Overview

The heliacal rise of a star occurs only once a year. The ancient Egyptians celebrated the day of the first morning of Sirius over the eastern morning horizon after a previous 65 to 70 days of invisibility with the Sothis festival . In its slightly too short calendar year, this event was delayed by one day in around four years. The numerous, partly exact dates for the heliacal rise of Sirius in ancient Egyptian sources , such as papyri and inscriptions, are therefore an important pillar of the ancient Egyptian royal chronology .

Even the early Mesopotamian priest astronomers observed heliacal rising of bright stars and Venus , but primarily for religious and cultic purposes.

It remains unclear whether the ancient Egyptians were aware in the early days or at all themselves that their (later) 365-day calendar led to the so-called Sothis cycle, and whether they knew its period length. However, the central role of the goddess Sopdet , who embodies Sirius, has been undoubtedly proven in calendar issues since the Old Kingdom , even in connection with the beginning of the year (first month of the new year: Wepet-renpet ).

The heliacal rise of Sirius did not migrate with the "Sothis year", but took place with astronomical regularity exactly after a sidereal year - but due to the precession of the earth's axis this gradually shifted, so that the heliacal rise of Sirius de facto already was about a month later in ancient times than in the Early Dynastic Period of Egypt. Originally, the heliacal rise of Sirius coincided with the beginning of the Egyptian year and the flood of the Nile at the beginning of summer - which is why the appearance of Sirius and Sopdet was later celebrated as the festival of the return of life.

background

Sidereal, tropical and 365-day calendar year

Between two heliacal rising of a fixed star (no proper motion), a star year or a sidereal year that is 365.2564 days long passes on average. Around this value there is a small fluctuation with the period of the earth's precession of about 26,000 years, because the precession changes the declination of the star and thus the time of its passage through the horizon. The day of the heliacal rise of Sirius runs through the 365-day calendar year of the ancient Egyptians, calculated without leap days, in an average of about 1424 years (365 ÷ (365.2564 - 365) = 1424). Through long-term observation is determined at the time 1,460 years, a value which is confirmed by modern astronomical calculations.

The value of 1460 years for the period of the Sothis cycle, which was valid at the time of the ancient Egyptians, happens to be the same as the period required for the vernal equinox, which the ancient Egyptians finally recognized as "correct" - but not applied - 365.25 To run through a calendar year of one day (365 ÷ (365.25 - 365) = 1460). “Correct” means to start the calendar year after the sun has passed through the spring equinox in the sky, a 365.2422 day long tropical year . The approximation of the calendar year with an average length of 365.25 days only became effective in the subsequent Julian calendar . With the more precise value of 365.2422 days for the tropical year, a cycle with a period of 1507 years can be specified for the one-time passage of the vernal equinox through the Egyptian calendar year.

The tropical year is the "natural" calendar year for a solar calendar. It always begins when the sun crosses the celestial equator in the vernal equator . This fictional star ( Aries point ) is not a fixed point in the sky. As a result of the precession of the earth, it moves slowly backwards (one orbit on the celestial equator in about 26,000 years), which is why the tropical year of the sun is slightly shorter than the sidereal year of the fixed stars.

Dependence of the day of the heliacal rise of Sirius on the geographical latitude

The apparent position of Sirius in the sky depends on the place of observation on earth and is additionally influenced by the earth's precession and Sirius' own movement. For example, at the present time Sirius cannot be seen from the North Pole to the 74th north latitude , while Sirius is constantly in the sky from the South Pole to the south 73rd parallel and does not set. Associated with this, starting from the 73rd northern degree of latitude, the maximum visible height above the horizon up to the region of the equator increases by one degree of altitude per degree of latitude to around 83 °, only to reduce to around 30 ° up to the south pole. In addition, the place of origin of Sirius changes depending on the latitude . At the 73rd north latitude, Sirius appears on the horizon in a south-easterly position (161 °), at the equator, however, almost in the east (106 °). The different visibility conditions have an effect on the observation time in the sky, which varies between about 140 minutes at the 73rd degree of north latitude and the constant presence at the South Pole, depending on the location. Similar conditions apply with regard to the latitude for the sunrise, which varies in time compared to the previous and the following day.

The geographical deviations have an individual “latitude-dependent Sothis cycle” for the area from the north 73rd to the south 73rd parallel, which also shows constant changes in the past or is subject to future deviations. Ancient Egypt comprised the region from the 24th to the 31st parallel north. Taking into account the given conditions, the possibility of a constant and simultaneous Sothis cycle was not given at any time in ancient Egypt either.

Observation site	Heliac rise	Rising azimuth	Maximum horizon height	Observation period
Dating of the worldwide heliacal rising of Sirius and maximum observation time
Wellington	June 9th	113 °	65 °	12 h
Rio de Janeiro	29th of July	108 °	50 °	10 h
Cairo	4th of August	109 °	43 °	9 h
Berlin	26th of August	118 °	20 °	7 h
Oslo	September 4th	125 °	13 °	6 h

Historical attempts at explanations

Egyptologist Karl Richard Lepsius

The ancient historians did not have the technical requirements of today's astronomy , which is why their calculations led to slight deviations in the result. Assuming that Sirius wandered by one day in the Egyptian calendar every four years, this resulted in the Sothis cycle of 1461 years (365.25 × 4) set in this way in the Julian calendar . The observation possibilities of modern astronomy show exact values, which therefore correct inaccuracies in the earlier estimates.

Since the scientific discovery of the Sothis cycle in connection with the Egyptian calendar in ancient Egypt , heated discussions among Egyptologists and historians regarding its importance for the Egyptians have been held up to the present day. The historical development, which was dominated by personal vanities, opinions and facts , repeatedly led to new perspectives of the Sothis cycle. A new study was published in 2017.

Some historians assumed that while Sirius formed the basis of the Egyptian calendar, it was not decisive for the introduction of the Egyptian calendar and that it was calculated in advance as the Sothis cycle. Another part of the researchers took the view that Sirius initially did not play an important role in the introduction of the Egyptian calendar and that the Sothis cycle was only noticed later. The connection between Sirius and Osiris was seen as the reason for the second assumption . The Egyptians therefore originally made a different assignment for Sirius in the early days of Egyptian history. In addition, the fact is stated that, due to the long duration of the Sothis cycle, at the time of the founding of the dynasties known to us, the entire duration of the cycle could not have been known.

Some researchers are of the opinion that Sirius only became an important part of the Egyptian calendar with the joint flood of the Nile and that it was therefore not integrated until later. The focus of the research has therefore been on trying to find enough evidence and clues as to what effects the Sothis cycle had on the Egyptian calendar. The consideration of the different starting points of the ancient calculation of the Sothis cycle, archaeological finds of records of the heliacal rising of Sirius and mathematical calculations of the Sothis cycle mark the historical path.

Origin of the name and dates

Goddess Sopdet

The origin of the name took its way from the original ancient Egyptian name of the goddess Sepdet / Sopdet,

spd.t (with vowels: * sắpd.˘t), which was later used in the first millennium BC. Became * sŏte / sote.

It remains unclear whether the meaning “the tip” was associated with the original ancient Egyptian constellation Sopdet, which in the early days included Sirius and two other stars . The corresponding Graecized case Σωτις for Sothis and naming Σείριος as "Seirios" for Sirius took place later Plutarch .

Both the dates of the Julian and the Gregorian calendar cannot be compared exactly with the Sothis information used in the Egyptian calendar. The ancient Egyptian day began with sunrise , the first visibility of the sun. The heliacal rise of Sirius, however, takes place at dawn before the first rays of sunshine. Correspondingly, the correction by one day must be taken into account for congruence. The same applies to the proleptic calendar.

Exploring the Sothis cycle in ancient times

Censorinus

Censorinus was a Roman author. He lived in the 3rd century AD and wrote his work "100 years after the time" when Emperor Antoninus Pius and Bruttius Praesens were consuls (139/140 AD) in the treatise "De Die Natali Liber" Censorinus calls the date of the heliacal rising with regard to the Sothis cycle:

“But the different years always begin on the first of the month they [d. H. the Egyptians] call Thoth . That day falls this year on the seventh day before the calendar of July [25. June], while 100 years ago, when Emperor Antoninus Pius was consul for the second time and Bruttius Praesens the other consul in Rome, this very day fell on the 13th day before the end of August. July],

At this time the [heliacal] rising of the Canicula [( Latin name for Sirius)] takes place in Egypt .

Now it is possible to determine "the great year ", as it was called in Egypt. "

- De Die Natali Liber, Chapter 21, 10-11

Otto Neugebauer and Richard Anthony Parker meanwhile assigned the term “great year” to the ancient Egyptian lunar calendar . The “big year” therefore refers to the respective leap years and not to the beginning of the Sothis cycle. The Papyrus Carlsberg 9 shows that AD 139 marked the 21st cycle year from July. The leap year as the “big year” began as early as July 138 AD as the 20th cycle year and ended in 139 AD with the season Heriu-renpet . The heliacal rising of Sirius fell in 139 AD on the last day of the season Heriu-renpet, which was followed by the Sothis festival on 1st Thoth at sunrise .

Censorinus made no reference to the heliacal rise of Sirius in his notes . In the years 1924 to 1926 Ludwig Borchardt traveled to Egypt to document the visibility of the heliacal rise. Among other things, he observed the heliacal rising of Sirius on August 3rd (Julian date July 21st) at 4:42 a.m. in Cairo in 1925 . Based on these and other observations by Ludwig Borchardt, a visual arc of around 9.5 ° for the location of Cairo could be determined for that time. The arc of vision of Sirius referred to the necessary minimum distance between the under the horizon standing sun and Sirius located on the visible sky to heliacal and akronychische to observe up or sunsets. According to Borchardt's team, the visual arc assumed up to this point could be reduced from 11 ° to 8.6 ° to 9.6 °.

Weather and air pollution can affect visibility conditions. The arc of vision today cannot, however, simply be transferred to the circumstances at that time. The more recent data used by parts of the historians therefore sometimes lead to incorrect results in calculations. For July 20, as the observation day of Censorinus, the following arcs of vision result for the reference locations in question, whereby only the region around Alexandria shows the Borchardt arcs of vision:

year	Alexandria	Cairo	Memphis	Thebes	Elephantine
Arc of Sight of Sirius on July 19 (July 20 in the Julian calendar)
239 AD	9.3 ° ( HA 4:29 am)	10.4 ° (no HA)	10.5 ° (no HA)	13.9 ° (no HA)	15.2 ° (no HA)
139 AD	9.3 ° (HA 4:28 am)	10.5 ° (no HA)	10.6 ° (no HA)	14.1 ° (no HA)	15.4 ° (no HA)

The choice of a different reference point in connection with the incorrect Sothis cycle calculation with 1460 years leads to incorrect dating of the events and to an incorrect setting of the Sothis cycle. Taking these circumstances into account, the Sothis cycle began before 139 BC. If Memphis served as a reference point in the New Kingdom. As early as 238 BC In the back calculation of Censorinus there was a deviation of at least one day since Ptolemy III. noted the heliacal ascent for the 1st Payni. The battle of Megiddo took place according to calculations of the Sothis cycle by Censorinus around 1501 BC. BC instead, although the campaign of Thutmose III. in the years between 1470 BC BC and 1456 BC Took place.

In addition, Censorinus' information does not coincide with the new moon day noted in the Egyptian lunar calendar during the campaign . The conclusion of Censorinus that the “great year” of the Egyptians was linked to July 20th has meanwhile been refuted by the astronomical data obtained. Nevertheless, some historians adopted Censorinus' conclusion for the calculation of the Sothis cycle. The Egyptologist Rolf Krauss therefore points to the view of Censorinus, which is still widespread today: “The fairy tale of a Sothis cycle of 1,460 Julian years with the day of rising July 19, which has been constant since ancient times, has been proven to be an arbitrarily created false construction”.

Theon of Alexandria

Theon of Alexandria was an ancient Greek astronomer and published the eleven-volume treatise on the Almagest by Claudius Ptolemy . According to Theon, the new Sothis cycle with a length of 1,460 years began in the fifth year of the principle of Augustus , which dates back to 26 BC. BC fell. Another handwritten note by Theon on a manuscript read: (Between) 100 years after the beginning of the Diocletian era and the beginning of the Sothis cycle are 1605 years . Theon himself did not give an exact date and was referring to the era of the 19th Dynasty . For these reasons, Theon's contradicting and imprecise statements do not allow an exact evaluation of his calculations.

Archaeological finds

Ivory tablets by Djer

The ivory tablet from Abydos

The rule of the ancient Egyptian king Djer is from 2952 BC. BC to 2880 BC BC or from 2999 BC. BC to 2952 BC BC. From his reign an ivory tablet was found in Abydos , on which the Egyptian goddess Sopdet can be seen as a seated cow with the symbol of the deity Shu between her horns as the embodiment of Sirius and the associated year.

Some Egyptologists see this ivory tablet as proof that the Sothis cycle must have been known before the first dynasty . Another justification for the theory of a Sothis cycle before the first dynasty (pre- or predynastic) is the assumption that the symbolic representation of the year would not have taken place without knowledge of a calendar based on Sopdet.

Ointment vessel from the Old Kingdom with the Sothis date

An ointment vessel apparently discovered in a private collection in 2014 names the Sothis rising; Month 4, Achet season, first day. At an assumed observation site Memphis indicates a time window from 2419 to 2406 BC. The style of the ointment vessel is dated to the 5th dynasty.

Papyrus al-Lahun

In 1899 a papyrus fragment from Lahun was published by Ludwig Borchardt , who named it after its place of discovery near the Fayum. Flinders Petrie had previously found many papyri. The two fragments of the Papyrus Berlin 10012 are relevant here: Borchardt translated part of the first fragment 10012A VS : “You should know that the heliacal rising of Sirius takes place on the 16th day of the fourth month in winter . Announce it to the priests of the city of Sechem-Sesostris-maa-cheru as well as Anubis on the mountain. ”In the second fragment 10012B there is the entry for the subsequent Sothis festival :“ Year 7 (of a nameless king), 17th Peret IV , Delivery of 200 breads and 60 mugs of beer. "

Borchardt now bordered the kings in question on Sesostris III. and Amenemhet III. a. After further investigation, he decided on Sesostris III. With regard to his decision, discussions arose in Egyptology as to whether Borchardt's decision was well founded. It was only after 1974 that Borchardt's assumption could finally be confirmed through the dating restrictions of other kings.

17th Dynasty graffito

A graffito from the Egyptian western desert of Gebel-Tjauti, which contains the report of an observation of the heliacal rise on the 20th of Schemu II, dates back to the 17th Dynasty . In addition, the 11th year of the reign of a king is mentioned, whose name has not survived. The observation was probably made from a plateau .

The 20th Schemu II is 19 days before the date of the 9th year of the reign of Amenhotep I ( 18th Dynasty ). If the sighting relates to Memphis, the heliacal rising took place between 1614 and 1610 BC. Instead of. If the observation came from Thebes, the year would be 1608 BC. To apply.

Ebers papyrus

Section of the Ebers papyrus

The Ebers papyrus was created in the period between 1530 BC. BC and 1501 BC Written in BC. In addition to medical topics and magic spells, it also contains information on the heliacal rise of Sirius. It was acquired by Georg Ebers in Luxor in 1873 for the Leipzig Museum and is now in the Leipzig University Library . In connection with the heliacal rise of Sirius it is noted there:

"In the ninth year of the reign of His Majesty, the King of Upper and Lower Egypt, Djeser-ka-re, may he live forever, the celebration of the New Year took place on the third month of summer, on the ninth day".

After initial difficulties in assigning this entry to the correct Egyptian king, an assignment to Amenhotep I could now be confirmed beyond doubt. Further investigations proved the age of the papyrus and thus a narrow time limit. The dates of the heliacal rise of Sirius represent another important pillar of the Egyptian royal chronology and are of great importance in connection with the Sothis cycle.

Nicolas Grimal calculated the heliacal rise of Sirius to be 1537 BC. And as the beginning of the rule of Amenhotep I the year 1546 BC. With coupling of the observation site to Memphis . In the event of the record in Thebes , Grimal estimated in 1526 BC. BC as the year of taking office.

Thutmose III.

Granite statue Thutmose III. in the Egyptian Museum Cairo

In the reign of Thutmose III. the heliacal rise of Sirius was also noted: "In the third month of summer, 28th day: on this day the celebration of the New Year of Sopdet." The information of the associated year of government has not been preserved. The date of the heliacal rising (27th Schemu III) is 18 days after the entry of Amenhotep I, which means a time difference between 70 and 75 years.

From the reign of Thutmose III. at the same time rarely mentioned new moon rises are preserved. The connection of all dates leads to a very precise delimitation of the reign and is thus a further confirmation of the correct assignment of the entry for Amenhotep I in the Ebers papyrus. The missing year of reign of Thutmose III. can now be determined more precisely through the exact classification.

Chronological significance of the papyri finds

Historians agree on the importance of the papyri finds. The entries of the heliacal rise of Sirius made it possible, on the one hand, to assign Sesostris III., Amenhotep I and Thutmose III could. In combination with the newly gained knowledge and as a result, more precise calculations could be carried out.

The reference from the Egyptian King Djer, on the other hand, was too general and did not allow a more precise date of the Sothis cycle; However, it was an important find because at that time the name Sirius was already known in the form of Sopdet as the year designation and thus represented evidence of a Sothis cycle that already existed at the time of Djer. In assessing the new state of affairs regarding the Sothis cycle, historians' opinions went in different directions.

Example of a typical papyrus in poor condition

There are many reasons for the different views: most archaeological discoveries took place in the period between the end of the 19th century AD and the first two thirds of the 20th century AD; this also causes most of the publications of the chronology. The Sothis cycle was assigned on the basis of these publications. The dating of the ancient historians initially contributed to different evaluations of the chronology. The papyri finds and the related dates of Sesostris III., Amenhotep I and Thutmose III. therefore initially took place within a framework of large temporal differences. The different weightings in the assessment of the "Sothis cycle" / "Archaeological calendar" systems were the main causes of the high deviations. More precise dating possibilities were offered in the last third of the 20th century AD by further discoveries and advances in the time determination of archaeological finds. Old theories and chronological approaches were discarded and new approaches developed. The Sothis cycle, actually a very precise dating instrument, was initially not judged according to astronomical principles, since more weight was attached to the archaeological determination of the age of the excavations. The result was an arbitrary start of the Sothis cycle at striking historical and chronological cuts in ancient Egypt. In the relevant publications, the beginning of the Sothis cycle was mostly described with the words “probably, could, possibly” and was thus the object of many theories that were intended to be substantiated in this way. An approximation of the astronomical realities of the Sothis cycle should only take place at the end of the 20th century AD.

Santorini volcano eruption

Santorini volcanic crater (modern times)

A number of critics have abandoned their initial skepticism about the dating based on the heliacal rise of Sirius. The majority of researchers take the dates as an important feature for determining the time of the Sothis cycle in connection with the Egyptian royal chronology . However, there are still skeptics who, for example, mark the Minoan eruption of the volcano on Santorini as the beginning of the 18th dynasty in Egypt and place the Sothis cycle in direct relation to it. Reference is also made to the " storm stele " of Ahmose I made. A natural catastrophe is reported: "Of tremendous roar and days of darkness all over Egypt", which corresponds to a typical side effect of a volcanic eruption. The disaster occurred between the eleventh and 22nd year of Ahmose's reign.

The relative chronology of the Minoan culture, which was already worked out by Arthur Evans and has been refined since then, was last linked in 1989 by Peter Warren and Vronwy Hankey, among others, with the fairly certain, absolute chronology of Egypt . Accordingly, the phase “Middle Minoan III” (MM III) with the Hyksos period , the phase “Late Minoan IA” (SM IA) with the end of the second intermediate period and “Late Minoan IB” (SM IB) with the time of Hatshepsut and Thutmose III. in connection. If this line of reasoning for the Minoan eruption is made about 30 years before the end of phase SM IA, the years 1530 to 1500 BC result. A possible approach, which in turn is the earliest possible first year of reign of Ahmose I for 1541 BC. Would mean.

The Egyptologists Rolf Krauss and Thomas Schneider set the first year of Ahmose I's reign to be 1539 BC. BC, with Wolfgang Helck for the ninth year of Amenophis I's reign a period between 1516 BC. BC and 1505 BC If Elephantine was chosen as reference place. Rolf Krauss and Thomas Schneider record in 1506 BC As the ninth year of reign from Amenophis I. A possible time corridor between 1530 BC results for the “storm stele” from these estimates. BC and 1516 BC Chr.

Deviations in the dating

The table shows possible dates in connection with the Sothis cycle, which lead to different dates in the Egyptian chronology :

Reference point	date	Possible dating	Comments and information
Sothis festival by Sesostris III.
Elephantine	???	1833 to 1830 BC Chr.	" 17th Peret IV in the seventh year of reign (Heliakischer Aufstieg: 16. Peret IV)"
Beginning of the 18th dynasty under Ahmose I.
Elephantine	???	1539 to 1536 BC Chr.	First year of the reign of Ahmose I (founder of the 18th dynasty)
Ahmose I. and the storm stele. Possible period in which the "thundering darkness" could occur
Elephantine	???	1530 to 1519 BC Chr.	Entry of Ahmose I. about "thundering darkness"
Heliacal rise of Sothis under Amenhotep I.
Elephantine	???	1506 to 1503 BC Chr.	" 9th Schemu III in the ninth year of reign (Sothis festival on 10th Schemu III)"
Sothis festival of Thutmose III. in Elephantine
Elephantine	???	1434 to 1431 BC Chr.	"28. Schemu III, without naming the year of government "

Exploring the Sothis Cycle in Modern Times

Eduard Meyer

Eduard Meyer published his dates in 1904 and put the first Sothis cycle in 4240 BC. He chose AD 139 as the base year and subtracted three cycles, each 1460 years, from AD 139. The use of three cycles was based on the assumption that the handling of a solar calendar by the Egyptians requires historical experience over a long period of time. Without further inclusion of the previous chronology followed for the years 2780 BC. BC and 1320 BC The further appointments according to his personal calculations. Like Eduard Meyer, Kenneth Anderson Kitchen took the view that the Sothis cycle in the Egyptian calendar had never been adjusted. He justified his theory, among other things, with the entry of the Nile flood under the Egyptian king Merenptah (see also Sothis cycle and the Nile flood ):

“In Deir el-Medina in West Thebes, a graffito from the first year of the reign of the Egyptian King Merenptah was found. The entry of the Nile flood can only be traced if the cycle began in the period between 2800 BC. BC and 2700 BC Is placed. After deducting the 1460 years that Censorinus calculated for the cycle length, in Merenptah's time there must therefore be another summer between 1340 BC. BC and 1240 BC Be assumed. The flood of the Nile is tied to summer, and this makes it impossible to postpone the chronological dates, as David Rohl calls for it ”.

The Egyptologists could not agree on when to start the Sothis cycle. Ludwig Borchardt's calculations in 1899 led to the first more reliable data for the Sothis cycle, which subsequently reduced the chronology of the second intermediate period from the previously assumed 400 years to a maximum of 200 years. The views of Eduard Meyer and Kenneth Kitchen rejected the majority of historians because the Sothis cycle did not fit the previous appointments of the Egyptian royal chronology. Flinders Petrie put the first cycle in the 4th dynasty , Parker in the 2nd dynasty , Alan Gardiner located it a dynasty later, while Herbert E. Winlock linked the dating with the reign of King Djoser . Other Egyptologists acted in the same way, such as B. William-Foxwell Albright and James H. Breasted , who wrote the beginning of the second Sothis cycle with the beginning of the 18th dynasty to the year 1580 BC. BC to 1560 BC BC, depending on the place of observation.

Manfred Bietak presented the results of the conference of the special research area SCIEM2000 in 2006 as part of the questions on Egyptian chronology . While the new empire and the 18th dynasty meanwhile have a largely stable chronology based on the Sothis cycle, the previous dating of the Egyptologists, with regard to the third intermediate period and the first millennium BC, shows BC, sometimes considerable deviations from archaeological evaluations.

Sothis observation site

When choosing the location for observing the heliacal rising of Sothis, at least one problem arose for the Egyptians: the Sothis rising did not take place at the same time. From the southernmost point of Ancient Egypt, Elephantine or Aswan , the heliacal sighting took place with a time delay in a northerly direction. In Alexandria , Sothis could not be seen until 6 to 7 days later. For the Egyptians, choosing a central location like Memphis meant that the announced dates were considered late for the south and premature for the north. Lepsius therefore considered a fixed reference point that shows only minimal deviations for all of Egypt. However, since no historical arguments could be found for this possibility, the Egyptologists deleted his considerations from the discussion.

Greco-Roman era

It is very likely that Memphis was the place of observation in the Greco-Roman era. A casual mention of the late antique author Olympiodorus from the 6th century AD makes this statement possible. According to him, the heliacal Sothis sighting was celebrated in Alexandria when "the star of the Memphites" rose. Olympiodors was interested in clarifying political questions in Egyptian history. The relevant calendar-astronomical questions did not fall into his field of research, which is why no distorting tendency can be seen in his reference.

The Egyptian chronology therefore initially assumed Memphis as a fixed reference point. In this context, it made sense to see Memphis as a cultural and economic center. However, more recent astronomical and historical data speak against Memphis as the "recording site of Sothis" in the early days of ancient Egypt.

Older eras

In contrast to the earlier traditional assumption of Memphis as the observation site, the sites Thebes and Elephantine / Aswan are now also being discussed. Both places allow a synchronous classification of the Ebers papyrus with the Egyptian chronology.

Sothis cycle and the flood of the Nile

Historic trip on the Nile

Numerous historians assume that the Sothis cycle was closely related to the Nile flood. The Nile flood is caused by the monsoon , which in Ethiopia and Sudan swells the Nile mainly from mid-May . The water masses reached Aswan at the beginning of June and later the Nile Delta at the end of June. The monsoon rainfall is subject to occasional fluctuations, which in Egypt led to delays in the long-awaited flooding of the Nile. From the rare records of the Nile flood in ancient Egypt, an example of the late arrival of the Nile flood is the entry of the Egyptian King Merenptah in the year of his coronation:

"Year 1, in the third month of Achet, day three: On this day ( 3rd Hathyr ) the water (Nile) caused the great flood."

The conversion of the entry shows for 1213 BC The heliacal rising of Sirius in Fayum on the 21st Thoth, which this year corresponded to the 7th July. Only 42 days later did the Nile flood with the 3rd Hathyr.

Heliacal rise of Sirius at the time of Ptolemy III.

Ptolemy III

The statement of Ptolemy III. from the year 238 BC Chr. Shows the background for the introduction of a leap day in order to anchor the state of the Egyptian calendar firmly: “The festivals of summer should be celebrated again in summer, the festivals of winter again in winter. It should be like it was a long time ago ”.

At the beginning of the first day in the tenth month, the " Beautiful Festival of the Desert Valley " was celebrated in Egypt . The festively clad Pharaoh invited the imperial god Amun, in the form of a sacred statue, to ride in a divine boat on the west side of the Nile. Several important burial sites were located there; including the Valley of the Kings and Queens and other important mortuary temples.

Observation site	year	Egyptian calendar	Egyptian date	Calendar date
Memphis	238 BC Chr.	1st day of the 10th month	01. Payni	July 14th

Mortuary temple of Mentuhotep II.

The crossing took place in the "shine" of the sun from east to west. Sirius, who embodied the Egyptian goddess Sopdet, had in 238 BC. Its heliacal rise at the beginning of the holy procession of the dead. This festival is documented for the first time under Mentuhotep II , during which the god Amun visited the western necropolis of Thebes in a solemn procession with the destination Deir el-Bahri . The common rise of the sun with Sirius at the beginning of the feast of the dead was a special and rare event, so that the insertion of a leap day of Ptolemy III. was in a striking connection.

The anchoring of the calendar in this constellation shows that the heliacal rise of Sirius for Ptolemy III. had no central meaning with regard to the Egyptian New Year and was not linked to the Nile flood. The resulting New Year dates for the year 238 BC Chr. Clarify the situation:

Observation site	year	Egyptian calendar	Egyptian date	Calendar date
Memphis	238 BC Chr.	1st day of the 1st month	01. Thoth	October 17th

The astronomical setting of the Sothis cycle

Calculation of the cycle lengths by Sirius

The Sothis cycle is divided into three areas: precession cycle, Sirius' own movement and change in sunrise times. The respective values of all three areas change individually with each epoch. The table shows the different values for the respective cycles. The exact mathematical values are rounded to full years.

Observation site	Year length	Cycle length	Remarks
Values from the 1st post-dynastic cycle in Egypt (beginning: Memphis 136 AD and Elephantine 161 AD)
Worldwide	365.25636 days	1424 years	Precession year , Sothis cycle without proper movement Sirius
Elephantine	365.25002 days	1460 years	Sirius year (precession and proper motion; actual Sothis cycle )
Elephantine	365.25086 days	1454 years	actual Sothis cycle plus the changed sunrise times
Memphis	365.25052 days	1457 years	actual Sothis cycle plus the changed sunrise times
Values from the 2nd dynastic cycle in Egypt (beginning: Memphis 1318 BC and Elephantine 1291 BC)
Worldwide	365.25636 days	1424 years	Precession year, Sothis cycle without proper movement Sirius
Elephantine	365.25002 days	1460 years	Sirius year (precession and proper motion; actual Sothis cycle )
Elephantine	365.25086 days	1455 years	actual Sothis cycle plus the changed sunrise times
Memphis	365.25121 days	1453 years	actual Sothis cycle plus the changed sunrise times
Values from the 1st dynastic cycle in Egypt (Elephantine 2774 - 1318 BC)
Worldwide	365.25636 days	1424 years	Precession year, Sothis cycle without proper movement Sirius
Elephantine	365.25002 days	1460 years	Sirius year (precession and proper motion; actual Sothis cycle )
Elephantine	365.25069 days	1456 years	actual Sothis cycle plus the changed sunrise times
Values from the predynastic cycle in Egypt (Elephantine 4236 - 2774 BC)
Worldwide	365.25636 days	1424 years	Precession year, Sothis cycle without proper movement Sirius
Elephantine	365.25089 days	1455 years	Sirius year (precession and proper motion; actual Sothis cycle )
Elephantine	365.25069 days	1456 years	actual Sothis cycle plus the changed sunrise times

Dating of the Sothis cycle

The annual dating always states the first year date of the heliacal rising of Sirius in the twelfth hour of the night of the previous day, which was followed with sunrise by the beginning of the Sothis festival on the next ancient Egyptian calendar day. After an average of almost four years, the date of the Sothis festival was shifted by one day in the ancient Egyptian calendar. In practice, this means that the heliacal ascent shifted in part after three years in the ancient Egyptian calendar.

Observation site	year	Egypt. calendar	Greg. calendar	Remarks
Sothis cycle: dates and places of observation
Memphis	2010	15. Achet IV	4th of August	New Year Celebration : 16th Achet IV (August 4th)
Memphis	1593	5. Heriu-renpet	July 31	Beginning of the second post-dynastic cycle
Memphis	136	5. Heriu-renpet	July 18th	Beginning of the first post-dynastic cycle
Memphis	1 v. Chr.	30. Schemu III	17th July	Comparison date of Thutmose III. ( Battle of Megiddo )
Elephantine	26 BC Chr.	16. Schemu III	10th of July	Introduction of the Julian calendar in Egypt
Memphis	84 BC Chr.	9. Scheme III	17th July	Comparison date of Amenhotep I. -Sothis date
Memphis	239 BC Chr.	29. Schemu I	July 14th	Canopus Decree Ptolemy III. 239 BC Chr.
Elephantine	1292 BC Chr.	5. Heriu-renpet	July 1	Beginning of the second dynastic cycle
Memphis	1319 BC Chr.	5. Heriu-renpet	July 6th	Beginning of the second dynastic cycle
Memphis	1458 BC Chr.	30. Schemu III	July 4th	Thutmose III. (1457 BC Battle of Megiddo )
Elephantine	1460 BC Chr.	24. Schemu III	June 28th	Thutmose III. (1457 BC Battle of Megiddo )
Elephantine	1520 BC Chr.	9. Scheme III	June 28th	Amenhotep I.
Memphis	1541 BC Chr.	9. Scheme III	July 4th	Amenhotep I.
Elephantine	1848 BC Chr.	16. Peret IV	June 26th	Sesostris III.
Memphis	1873 BC Chr.	16. Peret IV	2nd July	Sesostris III.
Elephantine	2748 BC Chr.	5. Heriu-renpet	18th of June	Beginning of the first dynastic cycle
Memphis	2777 BC Chr.	5. Heriu-renpet	25th June	Beginning of the first dynastic cycle

Analysis with regard to the setting up of the Sothis cycle

In view of the multitude of opinions that existed between 1838 and 1904 on the Sothis cycle, it was not surprising that Eduard Meyer saw the need to put the Egyptian royal chronology in a uniform framework. On the basis of Lepsius, with the support of Mahler, Borchardt and Weill, the first systematic chronology was created including the Sothis cycle.

At the present time, the majority of Egyptologists agree with Eduard Meyer's basic concept. A minority continues to doubt the existence of a continuous Sothis cycle in ancient Egypt. The reasons given are the difficulties in assigning the Egyptian royal chronology. In the meantime, however, it has been proven that it was not the Sothis cycle that was afflicted with inadequacies, but that the historical application of the Sothis cycle itself was the actual inadequacy. This knowledge is reflected in the publications of the Egyptian royal chronology.

The beginning of the 18th dynasty is dated to 1553 BC. BC to 1550 BC Dated; A comparison with the astronomical calculation for the first year of the reign of Ahmose I, the founder of the 18th dynasty, reveals no deviation from the previously used chronology for the observation site Fayum. For Sesostris III. the astronomical calculations are about 20 years away from the date by Jürgen von Beckerath. These deviations coincide with the time interval of the " 400 annual stele ", which by the dating of historians to the arrival of the Hyksos so far for the time between 1720 BC. BC and 1690 BC Was set; when the volcanic eruption of Santorini is classified around 1540 BC BC to 1520 BC In contrast, no time difference can be determined with regard to the “storm stele” as in the Ptolemaic dynasty.

The astronomical calculations of the Sothis cycle and their use for the chronology of the Egyptian kings have received majority approval in the present. Nevertheless, some researchers, such as Otto Neugebauer, point to problems in the practical application of the Sothis cycle. It is not known at which observation sites the recordings were made. The "intermediate times" in the Egyptian royal chronology offer a basis for discussion for the possibility of changing recording locations. The effects are minor, however, since the time differences averaged six days and thus only represent a fluctuation range of 21 to 27 years. Larger shifts in the Sothis cycle are not possible due to the astronomical conditions. In this respect, the instrument of astronomical calculation of the Sothis cycle provides the standard for possible arguments.

literature

Jan Assmann : Theology and wisdom in ancient Egypt. Fink, Munich 2005, ISBN 3-7705-4069-7 .
Ludwig Borchardt : The annals and the temporal determination of the Old Kingdom of Egyptian history (= sources and research on the determination of the time of Egyptian history. Volume 1, ZDB -ID 515285-9 ). Behrend, Berlin 1917.
WM Flinders Petrie : The royal tombs of the earliest dynasties: 1901. Part II (= Memoir of the Egypt Exploration Fund. Volume 21). Egypt Exploration Fund u. a., London 1901 ( digitization ).
Erik Hornung : Investigations into the chronology and history of the New Kingdom (= Egyptological treatises. Volume 11, ISSN 1614-6379 ). Harrassowitz, Wiesbaden 1964 (At the same time: University publication: Münster, Habil.-Schrift).
Rolf Krauss : Sothis and moon dates. Studies on the astronomical and technical chronology of ancient Egypt (= Hildesheimer Egyptological contributions. (HÄB). Volume 20). Gerstenberg, Hildesheim 1985, ISBN 3-8067-8086-X .
Manfred Kudlek, Erich H. Mickler: Solar and lunar eclipses of the Ancient Near East from 3000 BC to 0 (= Old Orient and Old Testament. Volume 1). Butzon and Bercker et al. a., Kevelaer u. a. 1971, ISBN 3-7666-8531-7 .
Ulrich Luft: Illahun Studies IV. On the chronological usability of the Sothis date. In: Studies on Ancient Egyptian Culture. (SAK). Volume 16, 1989, ISSN 0340-2215 , pp. 217-233.
Georg Möller: Hieratic palaeography. The development of Egyptian book script from the fifth dynasty to the Roman Empire. 2 volumes. 2nd improved edition. Hinrichs, Leipzig 1927–1936 (reprint: Zeller, Osnabrück 1965).
Johannes Neumann: The star of Bethlehem from the point of view of astronomy, history and ancient astrology. Neumann, Radebeul 2005, ISBN 3-9801264-3-9 .
O. Neugebauer : A History of Ancient Mathematical Astronomy. In three parts. (= Studies in the History of Mathematics and Physical Sciences. Volume 1). Springer, Berlin a. a. 2004, ISBN 3-540-06995-X .
Carl Riel: The sun and Sirius year of the Ramessids with the secret of the circuit and the year of Julius Caesar. Investigations into the ancient Egyptian normal year and the fixed years of the Greco-Roman time. Brockhaus, Leipzig 1875 (digitized version)
Thomas Schneider : Lexicon of the Pharaohs. Albatros, Düsseldorf 2002, ISBN 3-491-96053-3 , p. 115.
Siegfried Schott : Altägyptische Festdaten (= Academy of Sciences and Literature. Treatises of the humanities and social science class. (AM-GS). 1950, 10). Publishing house of the Academy of Sciences and Literature a. a., Mainz u. a. 1950.
Alexandra von Lieven : The sky over Esna. A case study on religious astronomy in Egypt using the example of the cosmological ceiling and architrave inscriptions in the temple of Esna (= Ägyptologische Abhandlungen. (ÄA). Volume 64). Harrassowitz, Wiesbaden 2000, ISBN 3-447-04324-5 (also: Tübingen, Univ., Master's thesis, 1998).

Marc Collier, Stephen Quirke (Eds.): The UCL Lahun Papyri. Volume 2: Marc Collier: Religious, Literary, Legal, Mathematical and Medical (= BAR. International Series. Volume 1209). Archaeopress, Oxford 2004, ISBN 1-84171-572-7 .

LE Doggett: Calendars. In: P. Kenneth Seidelmann (Ed.): Explanatory Supplement to the Astronomical Almanac. A Revision to the Explanatory Supplement to the Astronomical Ephemeris and the American Ephemeris and Nautical Almanac. Revised edition, 2nd printing. University Science Books, Sausalito 1992, ISBN 0-935702-68-7 , pp. 575-608 (reprinted ibid. 2006, ISBN 1-891389-45-9 ).

Kenneth Anderson Kitchen : The Chronology of Ancient Egypt. In: World Archeology. Volume 23, No. 2, 1991, pp. 201-208.

Richard A. Parker : The calendars of ancient Egypt (= Studies in Ancient Oriental Civilization. Volume 26, ISSN 0081-7554 ). University of Chicago Press, Chicago IL 1950.

Rita Gautschy, Michael E. Habicht , Francesco M. Galassi, Daniela Rutica, Frank J. Rühli, Rainer Hannig: A New Astronomically Based Chronological Model for the Egyptian Old Kingdom. In: Journal of Egyptian History. Volume 10, No. 2, 2017, pp. 69-118, doi : 10.1163 / 18741665-12340035 .

Web links

Commons : Category: Sopdet - Collection of pictures, videos and audio files

Commons : Sirius - album with pictures, videos and audio files

Wiktionary: Sirius - explanations of meanings, word origins, synonyms, translations

Alexandra von Lieven: Religious Astronomy in Ancient Egypt

Individual evidence

^ Rolf Krauss: Sothis and moon dates. Hildesheim 1985, p. 104.
↑ The dangerous goddess. according to: Alexandra von Lieven : Wine, women and song - rituals for the dangerous goddess. In: Carola Metzner-Nebelsick (Hrsg.): Rituals in prehistory, antiquity and the present. Studies in Near Eastern, Prehistoric and Classical Archeology, Egyptology, Ancient History, Theology and Religious Studies (= International Archeology: Working Group, Symposium, Conference, Congress 4). Interdisciplinary conference from 1st to 2nd February 2002 at the Free University of Berlin. Leidorf, Rahden 2003, ISBN 3-89646-434-5 , p. 47.
^ Heinrich Brugsch : Thesaurus inscriptionum Aegyptiacarum. = Ancient Egyptian inscriptions. Volume 1: Astronomical and astrological inscriptions of ancient Egyptian monuments. Collected, compared, transferred, explained and autographed. Hinrichs, Leipzig 1883, p. 86 (Unchanged reprint. Akademie-Druck- & Verlags-Anstalt, Graz 1968).
↑ Greek writers called the period from one Apokatastasis to the next Apokatastasis Sothis period ; according to Rita Gautschy: The star Sirius in ancient Egypt and in Babylon .
↑ Ecumenical Lexicon of Saints: Astronomical Calendar. Other calendars: Egypt (historical) heiligenlexikon.de
^ FK Ginzel: Handbook of mathematical and technical chronology. Leipzig 1906, § 39
^ AB Chace: The Rhind Mathematical Papyrus. Volume 1, Math. Assoc. of America, Oberlin, Ohio 1927, p. 44 ff.
^ MF Ingham: The Length of the Sothic Cycle. In: The Journal of Egyptian Archeology. Volume 55, 1969, p. 36.
↑ Southern Stars Systems SkyChart III , Saratoga, California 95070, United States of America.
^ Rolf Krauss: Sothis and moon dates. Hildesheim 1985, pp. 201-203.
↑ Maximum observation time in the night sky at evening sunrise
^ Rita Gautschy, Michael E. Habicht, Francesco M. Galassi, Daniela Rutica, Frank J. Rühli: A New Astronomically Based Chronological Model for the Egyptian Old Kingdom . In: Journal of Egyptian History . tape 10 , no. 2 , November 17, 2017, ISSN 1874-1665 , p. 69-108 , doi : 10.1163 / 18741665-12340035 ( brillonline.com [accessed November 24, 2017]).
↑ Deducting six days from July 1st results in June 25th in the year 238 AD, cf. the day counting method of the " inclusive counting "
↑ If the twelve days from August 1st are subtracted, the result is July 20th, 139 AD; see. the day counting method of the "inclusive counting".
↑ ¹⁰ Sed horum initia semper a primo die mensis eius sumuntur, cui apud Aegyptios nomen est Thouth, quique hoc anno fuit ante diem VII kal. Jul., Cum abhinc annos centum imperatore Antonino Pio II Bruttio Praesente Romae consulibus idem dies fuerit ante diem XIII kal. Aug., a quo tempore solet canicula in Aegypto facere exortum. ¹¹ [ALT imaginis: Legamen ad hanc sectionem in lingua gallica] Quare scire etiam licet anni illius magni, qui, ut supra dictum est, solaris et canicularis et dei annus vocatur, nunc agi vertentem annum centensimum according to the original text by Censorinus online
^ Rolf Krauss: Sothis and moon dates. Hildesheim 1985, pp. 3-7.
^ Siegfried Schott: Ancient Egyptian festival dates. Mainz u. a. 1950, p. 18.
^ Rolf Krauss: Sothis and moon dates. Hildesheim 1985, p. 54.
^ Raymond Weill : Bases, méthodes and résultats de la Chronologie Égyptienne. Geuthner, Paris 1926, p. 9; and: Raymond Weill: Compléments. Geuthner, Paris 1928. Weill refers to C. Ptolemy's Canon of the Kings, Volume IV.
^ WM Flinders Petrie: The royal tombs of the earliest dynasties: 1901. Part 2. London 1901, p. 22; see also the original illustration by Francesco Raffaele .
↑ Michael E. Habicht, Rita Gautschy, Renate Siegmann, Daniela Rutica, Rainer Hannig: A New Sothis Rise on a Small Cylindrical Jar from the Old Kingdom. In: Göttinger Miscellen. 247, 2015, pp. 41-50.
^ John Coleman Darnell: Theban desert road survey in the Egyptian western desert. Volume 1: Gebel Tjauti rock inscriptions 1-45 and Wadi el-Ḥôl rock inscriptions 1-45 (= Oriental Institute Publications. 119). Oriental Institute of the University of Chicago, Chicago IL 2002, ISBN 1-885923-17-1 , pp. 49-52.
↑ Nicolas Grimal: Histoire de l'Égypte Ancienne. Fayard, Paris 1988, ISBN 2-213-02191-0 , Chapitre IX: Les Thoutmosides. (on-line)
↑ Karen Polinger-Foster, Robert K. Ritner, Benjamin R. Foster: text, storms and the Thera eruption. In: Journal of Near Eastern Studies Volume 55, No. 1, 1996, pp. 1-14.
↑ According to Jürgen von Beckerath's dating, this would result in the period between 1539 BC. BC to 1528 BC Surrendered.
↑ The Hyksos were driven out in the 18th and 19th centuries. Year of reign of Ahmose.
↑ In: An extract from Professor Kitchen's widely circulated letter ; from: Waste Of Time .
^ WM Flinders Petrie: The royal tombs of the earliest dynasties: 1901. Part 2. London 1901.
^ Alan Gardiner : Egypt of the Pharaohs. An Introduction. Clarendon Press, Oxford 1961.
^ Herbert E. Winlock : Models of Daily Life in Ancient Egypt. From the Tomb of Meket-Rēʿ at Thebes (= Publications of the Metropolitan Museum of Art. Egyptian Expedition 18, ZDB -ID 275440-x ). Harvard University Press, Cambridge MA 1955.
^ William Foxwell Albright : From the Stone Age to Christianity. Monotheism and historical becoming. Lehnen, Munich 1949, p. 166.
↑ James H. Breasted : A History of Egypt from the Earliest Times to the Persian Conquest. Scribner's Sons, New York 1905.
^ Egypt & Time SCIEM2000: Workshop Precision of the historical Chronology ; Vienna June 30th - July 2nd 2005.
^ Graffito 862 from Theben West.
↑ Otto Kaiser (Ed.): Texts from the environment of the Old Testament . Old series, Volume 1, Gütersloher Verlags-Haus, Gütersloh 1982ff.
↑ corresponds to July 18 in the proleptic Julian calendar
↑ See also: Erik Hornung: The night journey of the sun. An ancient Egyptian description of the afterlife. Artemis & Winkler, Zurich a. a. 1991, ISBN 3-7608-1036-5 .
↑ Siegfried Schott: The beautiful festival of the desert valley. Festive customs of a city of the dead (= Academy of Sciences and Literature. Treatises of the humanities and social sciences class 1952, 11, ISSN 0002-2977 ). Publishing house of the Academy of Sciences and Literature, Mainz 1953.
↑ corresponds to October 21 in the proleptic Julian calendar
↑ Calculations based on the 360 ° definition of the tropical year (at the beginning of 2000 it was 365.2422 days) (see tropical year )
↑ based on a 365.00 daily calendar
↑ Herbert Donner : History of the people of Israel and its neighbors in outline. Volume 2: From the royal era to Alexander the great. With an outlook on the history of Judaism to Bar Kochba (= floor plans for the Old Testament. Volume 4, 2). 3rd, revised and supplemented edition. Vandenhoeck & Ruprecht, Göttingen 2001, ISBN 3-525-51680-0 .
↑ Helmut Freydank : Texts on legal and economic life (= texts from the environment of the Old Testament. (TUAT). New series, volume 1). Gütersloher Verlags-Haus Mohn, Gütersloh 2004, ISBN 3-579-05289-6 , p. 358 based on: Jürgen von Beckerath : Chronology of Pharaonic Egypt. The timing of Egyptian history from prehistoric times to 332 BC BC (= Munich Egyptological Studies. Volume 46). von Zabern, Mainz 1997, ISBN 3-8053-2310-7 .
↑ cf. the same statement by Jean Vercoutter in: Elena Cassin , Jean Bottéro , Jean Vercoutter (eds.): The ancient oriental empires. Volume 1: From the Palaeolithic to the middle of the 2nd millennium (= Fischer world history. Volume 2). Fischer-Taschenbuch-Verlag, Frankfurt am Main 1965, pp. 351–352.

This version was added to the list of articles worth reading on August 28, 2009 .

[1] Rolf Krauss: Sothis and moon dates. Hildesheim 1985, p. 104.

[2] The dangerous goddess. according to: Alexandra von Lieven : Wine, women and song - rituals for the dangerous goddess. In: Carola Metzner-Nebelsick (Hrsg.): Rituals in prehistory, antiquity and the present. Studies in Near Eastern, Prehistoric and Classical Archeology, Egyptology, Ancient History, Theology and Religious Studies (= International Archeology: Working Group, Symposium, Conference, Congress 4). Interdisciplinary conference from 1st to 2nd February 2002 at the Free University of Berlin. Leidorf, Rahden 2003, ISBN 3-89646-434-5 , p. 47.

[B-3] Heinrich Brugsch : Thesaurus inscriptionum Aegyptiacarum. = Ancient Egyptian inscriptions. Volume 1: Astronomical and astrological inscriptions of ancient Egyptian monuments. Collected, compared, transferred, explained and autographed. Hinrichs, Leipzig 1883, p. 86 (Unchanged reprint. Akademie-Druck- & Verlags-Anstalt, Graz 1968).

[4] Greek writers called the period from one Apokatastasis to the next Apokatastasis Sothis period ; according to Rita Gautschy: The star Sirius in ancient Egypt and in Babylon .

[5] Ecumenical Lexicon of Saints: Astronomical Calendar. Other calendars: Egypt (historical) heiligenlexikon.de

[6] FK Ginzel: Handbook of mathematical and technical chronology. Leipzig 1906, § 39

[7] AB Chace: The Rhind Mathematical Papyrus. Volume 1, Math. Assoc. of America, Oberlin, Ohio 1927, p. 44 ff.

[8] MF Ingham: The Length of the Sothic Cycle. In: The Journal of Egyptian Archeology. Volume 55, 1969, p. 36.

[Sky-9] Southern Stars Systems SkyChart III , Saratoga, California 95070, United States of America.

[10] Rolf Krauss: Sothis and moon dates. Hildesheim 1985, pp. 201-203.

[11] Maximum observation time in the night sky at evening sunrise

[12] Rita Gautschy, Michael E. Habicht, Francesco M. Galassi, Daniela Rutica, Frank J. Rühli: A New Astronomically Based Chronological Model for the Egyptian Old Kingdom . In: Journal of Egyptian History . tape 10 , no. 2 , November 17, 2017, ISSN 1874-1665 , p. 69-108 , doi : 10.1163 / 18741665-12340035 ( brillonline.com [accessed November 24, 2017]).

[13] Deducting six days from July 1st results in June 25th in the year 238 AD, cf. the day counting method of the " inclusive counting "

[14] If the twelve days from August 1st are subtracted, the result is July 20th, 139 AD; see. the day counting method of the "inclusive counting".

[15] ¹⁰ Sed horum initia semper a primo die mensis eius sumuntur, cui apud Aegyptios nomen est Thouth, quique hoc anno fuit ante diem VII kal. Jul., Cum abhinc annos centum imperatore Antonino Pio II Bruttio Praesente Romae consulibus idem dies fuerit ante diem XIII kal. Aug., a quo tempore solet canicula in Aegypto facere exortum. ¹¹ [ALT imaginis: Legamen ad hanc sectionem in lingua gallica] Quare scire etiam licet anni illius magni, qui, ut supra dictum est, solaris et canicularis et dei annus vocatur, nunc agi vertentem annum centensimum according to the original text by Censorinus online

[16] Rolf Krauss: Sothis and moon dates. Hildesheim 1985, pp. 3-7.

[17] Siegfried Schott: Ancient Egyptian festival dates. Mainz u. a. 1950, p. 18.

[18] Rolf Krauss: Sothis and moon dates. Hildesheim 1985, p. 54.

[19] Raymond Weill : Bases, méthodes and résultats de la Chronologie Égyptienne. Geuthner, Paris 1926, p. 9; and: Raymond Weill: Compléments. Geuthner, Paris 1928. Weill refers to C. Ptolemy's Canon of the Kings, Volume IV.

[20] WM Flinders Petrie: The royal tombs of the earliest dynasties: 1901. Part 2. London 1901, p. 22; see also the original illustration by Francesco Raffaele .

[21] Michael E. Habicht, Rita Gautschy, Renate Siegmann, Daniela Rutica, Rainer Hannig: A New Sothis Rise on a Small Cylindrical Jar from the Old Kingdom. In: Göttinger Miscellen. 247, 2015, pp. 41-50.

[22] John Coleman Darnell: Theban desert road survey in the Egyptian western desert. Volume 1: Gebel Tjauti rock inscriptions 1-45 and Wadi el-Ḥôl rock inscriptions 1-45 (= Oriental Institute Publications. 119). Oriental Institute of the University of Chicago, Chicago IL 2002, ISBN 1-885923-17-1 , pp. 49-52.

[23] Nicolas Grimal: Histoire de l'Égypte Ancienne. Fayard, Paris 1988, ISBN 2-213-02191-0 , Chapitre IX: Les Thoutmosides. (on-line)

[24] Karen Polinger-Foster, Robert K. Ritner, Benjamin R. Foster: text, storms and the Thera eruption. In: Journal of Near Eastern Studies Volume 55, No. 1, 1996, pp. 1-14.

[25] According to Jürgen von Beckerath's dating, this would result in the period between 1539 BC. BC to 1528 BC Surrendered.

[26] The Hyksos were driven out in the 18th and 19th centuries. Year of reign of Ahmose.

[27] In: An extract from Professor Kitchen's widely circulated letter ; from: Waste Of Time .

[28] WM Flinders Petrie: The royal tombs of the earliest dynasties: 1901. Part 2. London 1901.

[29] Alan Gardiner : Egypt of the Pharaohs. An Introduction. Clarendon Press, Oxford 1961.

[30] Herbert E. Winlock : Models of Daily Life in Ancient Egypt. From the Tomb of Meket-Rēʿ at Thebes (= Publications of the Metropolitan Museum of Art. Egyptian Expedition 18, ZDB -ID 275440-x ). Harvard University Press, Cambridge MA 1955.

[31] William Foxwell Albright : From the Stone Age to Christianity. Monotheism and historical becoming. Lehnen, Munich 1949, p. 166.

[32] James H. Breasted : A History of Egypt from the Earliest Times to the Persian Conquest. Scribner's Sons, New York 1905.

[33] Egypt & Time SCIEM2000: Workshop Precision of the historical Chronology ; Vienna June 30th - July 2nd 2005.

[34] Graffito 862 from Theben West.

[35] Otto Kaiser (Ed.): Texts from the environment of the Old Testament . Old series, Volume 1, Gütersloher Verlags-Haus, Gütersloh 1982ff.

[18._Juli-36] rresponds to July 18 in the proleptic Julian calendar

[37] See also: Erik Hornung: The night journey of the sun. An ancient Egyptian description of the afterlife. Artemis & Winkler, Zurich a. a. 1991, ISBN 3-7608-1036-5 .

[38] Siegfried Schott: The beautiful festival of the desert valley. Festive customs of a city of the dead (= Academy of Sciences and Literature. Treatises of the humanities and social sciences class 1952, 11, ISSN 0002-2977 ). Publishing house of the Academy of Sciences and Literature, Mainz 1953.

[21._Oktober-39] rresponds to October 21 in the proleptic Julian calendar

[40] Calculations based on the 360 ° definition of the tropical year (at the beginning of 2000 it was 365.2422 days) (see tropical year )

[41] sed on a 365.00 daily calendar

[42] Herbert Donner : History of the people of Israel and its neighbors in outline. Volume 2: From the royal era to Alexander the great. With an outlook on the history of Judaism to Bar Kochba (= floor plans for the Old Testament. Volume 4, 2). 3rd, revised and supplemented edition. Vandenhoeck & Ruprecht, Göttingen 2001, ISBN 3-525-51680-0 .

[43] Helmut Freydank : Texts on legal and economic life (= texts from the environment of the Old Testament. (TUAT). New series, volume 1). Gütersloher Verlags-Haus Mohn, Gütersloh 2004, ISBN 3-579-05289-6 , p. 358 based on: Jürgen von Beckerath : Chronology of Pharaonic Egypt. The timing of Egyptian history from prehistoric times to 332 BC BC (= Munich Egyptological Studies. Volume 46). von Zabern, Mainz 1997, ISBN 3-8053-2310-7 .

[44] . the same statement by Jean Vercoutter in: Elena Cassin , Jean Bottéro , Jean Vercoutter (eds.): The ancient oriental empires. Volume 1: From the Palaeolithic to the middle of the 2nd millennium (= Fischer world history. Volume 2). Fischer-Taschenbuch-Verlag, Frankfurt am Main 1965, pp. 351–352.