Constellations Thesis Book by Nesrin Zidan

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Evidently, during the Ptolemaic
era, the zodiac was introduced to Egypt,
and eventually, the decans were just
names for the thirds of a zodiac sign.
True astronomical manuscripts also
emerge in this most recent time, although
they cannot be said to be of Egyptian
origin since they were already introduced
by the Babylonians and developed by the
Greeks.
Furthermore, texts that were
found in the pyramid of Unas, the last
king of the fifth Dynasty, depict the night
with an emphasis on three stars. It is believed
that this was the Egyptians’ introduction
to star clocks, which is estimated
to have taken place after the development
of the civil calendar by the 24th century
BC (Parker, 1974). There are two types
of star clocks. It is not until 2150 BC,
that we learn how the first type of clock
functions. We learn that there is a total of
12 hours at night, from diagrams on the
inside of coffin lids, which were named
‘diagonal calendars’ in their conception
early on. The mechanism behind these
clocks is that they consist of 36 intervals
of 10 days, with a total of 360 days and
12 stars per interval (one for each hour
in the night). The second type of clock
is found on the walls of Ramesside stone
tombs dating back to the twelfth century
BC. This clock is made up of 24 intervals
in 15 days, again for a total of 360 days,
but with 13 stars per interval (one for
each hour in the night, and an extra one
for the beginning of the night) (Depuydt,
1998).
Fig. 2.4. Illustration of Ramses II