systematic observations of the sky might be more suitable
than astronomy. Th en again, astronomy has a historical
dimension. Before it became complex, it had to be simple.
A full appreciation of astronomy involves a proper under-
standing of where the subject was at every stage of its evolu-
tion, even in its small beginnings.
One reason that Egyptian astronomy could not have
been truly scientifi c is that trigonometry had not yet been
discovered. Th e Greek astronomer Hipparchus discovered
it in the second century b.c.e. Trigonometry relates angle
and distance to each other. In observing the sky, one cannot
measure the distance between the zenith (the point in the
sky right above us) and a point on the horizon or between
a point on the horizon and a certain star. In trigonometry
it is not the distances themselves that matter but the rela-
tion between distances and angles. Th e numbers of trigo-
nometry are mostly irrational, meaning that they cannot be
expressed in fractions featuring whole numbers. Without
such irrational numbers, a true scientifi c astronomy is im-
possible. Nowhere in hieroglyphic writing is there a trace of
irrational numbers.
Ancient Egyptian texts and images are replete with ref-
erences to the night sky and what happens there. Strictly
speaking, these texts and images are not astronomical. Still,
they, too, contribute to our understanding of how Egyptians
viewed the night sky. Th ey were understandably fascinated by
the disks of light and the twinkling dots, even if they did not
understand their true nature. As a result, they interpreted the
movements in the sky in terms of tales populated by divine
characters. Among the earliest such interpretations are the
texts inscribed on the walls of the inner rooms of the pyra-
mids dating to the third millennium b.c.e. It is no longer pos-
sible to reconstruct fully what these authors saw and why they
saw it in the star sky, just as it is not clear why someone sees
a certain shape in a certain cloud. Th is may account for the
frustrating incomprehensibility of much of the so-called Pyr-
amid texts, a collection of ancient Egyptian religious texts.
A remarkable section in the Pyramid texts is the Cannibal
hymn. Th e contents of this hymn are unique in Egyptian lit-
erature. Th ere is mention of slaughtering fi rstborn children,
slitting throats, eating organs, cooking body parts, using
victims for kindling, and lighting fi res with thighs. On the
surface, there is no way of interpreting its contents charitably,
yet the hymn may be nothing more than a description of how
the sun dims the light of the stars—that is, eats the stars, so
to speak—when it rises in the morning. In fact, much of the
texts found in pyramids appear to concern an eff ort to inter-
pret the movements of the stars.
Th e best represented type of early-period astronomical
text is the so-called star clock. Star clocks, of two main types,
are found in tombs. Th e fi rst type appears on the insides of
coffi n lids dating to about 2100–1900 b.c.e. In this type, the
year is subdivided into 36 intervals of 10 days, for a total of
360 days. Twelve stars are listed for every 10-day period, one
each for every hour of the night. Th e second type of star clockInner coffi n of the priest Hornedjitef, Th ebes, Egypt (third century
b.c.e.); the coffi n lid interior is decorated with fi gures relating to
astronomy. (© Th e Trustees of the British Museum)
astronomy: Egypt 125