An ancient Egyptian Papyrus–the so-called Cairo Calendar–is perhaps one of the most fascinating pieces of evidence of how advanced the ancient Egyptians were in terms of Astronomy.

Also known as the Calendar of the Days of Luck and the Unfortunate, this papyrus – which dates from 1244 – 1163 BC, assigns predictions and forecasts to every day of the Egyptian year.

These forecasts indicate whether the day or part of the day is considered “good” or “bad.”

The papyrus also contains information about astronomical observations of the day, such as the behavior of astronomical objects, especially Algol–designated Beta Persei–also known as the Demon Star.

Algol is a bright multiple star in the constellation of Perseus and one of the first non-nova variable stars to be discovered.

A Fusion Between Myth And Science

Now, researchers believe that the astronomical symbolism discovered in the two oldest myths of Egypt suggests that similar clues could be found in other ancient Egyptian texts.

The article, published in ‘De Gruyter – Open Astronomy,’ looks at how the myths of the Egyptian deities Horus and Set were used in the calendar.

“Algol as Horus in the Cairo Calendar: the possible means and the motives of the observations” by Sebastian Porceddu, Lauri Jetsu, Tapio Markkanen, Joonas Lyytinen, PerttuKajatkari, Jyri Lehtinen, and Jaana Toivari-Viitala takes an unprecedented look at how ancient Egyptian deities such as Horus and Set were used in the ancient papyrus and what it signified for people thousands of years ago, as well as the connection between astronomical objects and stars.

The new article aims at demonstrating how ancient Egyptian calendars (not only the Cairo Calendar) were used to describe the behavior of astronomical observations, in particular, the star system Algol.

However, almost nothing is known about who registered the Algol period in the Cairo calendar, nor how it was achieved, thousands of years ago.

The authors show how the ancient Egyptian scribes present the celestial phenomena as the activity of the gods, which reveals why Algol received the title of Horus.

The new paper offers ten arguments that prove that the ancient Egyptian scribes, known as the “observers of the hour” had the means and possible motives to register the Algol period in the Cairo calendar.

“The discovery of Algol’s variability would have to be dated to thousands of years earlier than has been previously known. The star would have been a part of ancient Egyptian mythology as a form of the god Horus,” explained one of the study’s authors Sebastian Porceddu from the University of Helsinki.