Just as we have newspaper horoscope columns that tell us what will happen to us on a particular day, the ancient Egyptians had special calendars that told them what to do on each day of the year. Unlike our modern horoscopes, which apply to individuals, these calendars applied to everyone. If the calendar advised you not to go out of your house on a particular day, then everyone stayed inside.
The Egyptian calendar was slightly different from ours. There were only three seasons: (1) Inundation or Akhet (2) Emergence or Proyet, Which was when the water receded. (3) Summer Shomu.
Each of these seasons had 4 months of 30 days each, so that there were 360 days to the standard year. While the Egyptians did not realize that the earth rotates around the sun, they did know that a calendar of 360 days would soon be out of phase with nature. For every year that passes, periodic natural phenomena will seem off by 5 days. If you are using a 360 calendar eventually the season you would call "Inundation" would come when the land was dry, because the Nile starts to overflow its banks every 365 days. To correct for this discrepancy, the Egyptians at the beginning of every year had 5 "added days." Thus the Egyptian calendar was really a 365 day calendar.
New Year's Day, which was called "The Opening of the Year," dawned with an astronomical event which took place on June 21 in about 3000 B.C. The brilliant star Sirius became visible just before dawn. This event was called "The going up of the Neteret Sothis."
In 1943 a rolled up Papyrus was bought by the Cairo museum from an Antiquities dealer. It was written in Hieratic and, while portions of it were eaten away by ants, it was clear that the papyrus dealt with the days of the year and what was going to happen on them. The papyrus actually contained three separate books on this theme. The first and the third were badly damaged, but the second is almost complete for each day of the year has come to be known as the Cairo Calendar.
The title of the Cairo Calendar is "An Introduction to The Start Everlastingness and The End of Eternity."
For each day of the year there is a reading usually of three parts in a more or less consistent order:
1. The first part states the days auspice: "Favorable", "Mostly Favorable", "Very Favorable", "Adverse," "Mostly Adverse," and "Very Adverse." Most of the days of the Cairo calendar are either "Very Favorable" or "Very Adverse." A few days, however, seem to be partially "Favorable" and partially "Adverse."
2. The auspice is determined by the second part which describes what mythological event took place on that day. For example, on the day when the first part, the auspice, is "Very Adverse" the second part usually describes an unhappy or even a violent happening in the life of the Neteru, such as Heru fighting with Set and losing His eye. When the auspice is "Favorable", the day was generally one of peace or of partying in heaven.
3. The third part of the reading tells how to behave as a result of the auspice and the mythological event. On the day Heru's eye is lost, a bad day, you are told not to go out of your house.
In some places the mythological portions are quite difficult to follow. Many minor Neteru are refereed to and, while they were undoubtedly recognizable to the Ancient Egyptians, They seem remote to the modern reader. Also, the calendar does not tell one sequential mythological story. One theme continues for three or four days, and then ends abruptly to be replaced by a completely different theme.
The Cairo Calendar is difficult to interpret for other reasons as well: the papyrus is damaged in several places making some readings impossible; there are scribal errors; and at times the meanings of words themselves are obscure. Because of these difficulties some liberties have been taken with the translation which is based on the transcription from the hieratic by Prof. Bakir, who first published the calendar. In some places, totally incomprehensible phrases are omitted - ellipses indicate missing or unreadable text.
On the following site, the Cairo calendar is reproduced in a form that will enable you to look at each day to see if the Egyptians believed it to be favorable or unfavorable, what the important mythological event was, and, as a consequence, what actions should or should not be taken.
We don't think We have to tell you that the star Sirius rises at different times in different places. Due to this fact, We can only provide you with the dates according to the ancient calendar. Sure, we could do it to make it easier on you, but we tried doing it for three days straight without any luck and a lot of hair pulling. Our suggestion to you, if you wish to follow this calendar, would be to join a group (most of them have their own calendars based on the date that Sirius rises locally) and combine the two calendars for easier use.
Otherwise, I hope the day you see this is a "Very Favorable" one.