The ancient Egyptians’ astronomical skills and ability to
calculate positions of celestial bodies and eclipses has been
Because the Babylonians have left us far more
astronomical records than the Egyptians, it became a modern
myth, that the Ancient Egyptian celestial science could not
compete with the elaborated astronomy of the Babylonians.
But to all these learned sky watchers of the past it
was a sacred science.
Egyptian star gods. Late period.
Ancient Egyptian ability to calculate positions of celestial
bodies and eclipses
Greek historian Diodorus Siculus stated (c. 20 BC) categorically
that the ancient Egyptian astronomers possessed the ability to
predict solar eclipses. Greek author and scholar Plutarch
(46-125 AD) related that the ancient Egyptians explained solar
eclipses by the passage of the Moon between the Sun and the
Earth in daylight hours. Further, the famous “Vienna Papyrus”
describes lunar and solar eclipses and their implications and
presents great knowledge of astronomy.
More so, Greek-Egyptian scholar and Father of Church, Clement of
Alexandria (150-215 AD), relates to temple libraries containing
a 50-volume book-series “of Thoth” preserved by the priests of
ancient Egypt - four of them treating astronomical subjects. One
book dealt with the “constitution of the Sun and Moon” and
another “the conjunctions and variations of the light of the Sun
and Moon”. In these books it was axiomatic that it was a valued
skill of the ancient Egyptian astronomer-priests to predict
The books were collected by the founder of the Alexandrian
library, king Ptolemy II, c. 300 BC, from all of Egypt's ancient
temple libraries - texts far more ancient than any early Greek
influence. Later, by his access to these valuable sources the
Egyptian-Greek historian, hieroglyph scholar, and stoic
philosopher Chaeramon of Alexandria, who was the chief librarian
of the Alexandrian Library, c. 40 AD wrote several treatises on
the stars of heaven and on comets, etc.
Part of the vizier Senmut’s star map, c. 1500 BC.
Observations of planets “travel backwards”
The very existence of the precise planetary positions on the
Senmut star map, and on other star maps of that era c. 1500-1300
BC, demonstrates an expertise concerning the calculations of
planetary positions. The fact that these maps include such
details as a retrograde planet - Mars - and a solar eclipse
position (proven to be exactly as stated on the Senmut map),
exclude any possibility of coincidence.
A thousand years before the time of Senmut, the
astronomer-priests were developing such skills by constant
observation of the firmament, which necessitated the keeping of
accurate records, especially with regard to calculating
celestial positions and cyclic phenomena. The data were used for
the sun- and star-related calendars as well as the “star clock”.
Records of such astronomical calculations, however, do not seem
to have survived, although there are examples of very ancient
calendars. But as documented by e.g. inscriptions - a planet
“...travels backwards...” - a retrograde movement of a planet
placed opposite to the sun was a well-known phenomenon.
The precise positioning of planets by observing them, even in
bright daylight, from the bottom of deep wells or shafts
directly (and probably less by oblique mirror-reflection in a
water surface in the well), was a widely known practice in all
Furthermore, one of
the oldest known Egyptian presentations of a planetary position,
places Jupiter close to the decan (celestial sector of
10-degrees) of Sirius. This dates back some 4200 years, and is
recorded on a fragment of a starclock-diagram depicted inside a
coffin-lid (on Heny's coffin) - one of the traditional methods
Babylon, 721 BC, the hitherto oldest finding of recorded lunar
astronomical observations from a well - is not a myth
It has been doubted - under the modern
time's drawback of historical knowledge - and has been called “a
myth”, that astronomers of ancient times used wells/shafts at
all, in order to make observations from them. Plato (428-348 BC)
mentions that the philosopher Thales of Miletus (c. 640-547 BC)
had an accident in a well while observing the stars. - And the
Greek author Aesop (6th c. BC) tells similarly concerning
another astronomer in a well-shaft.
An ancient apocryphal text, c. 100 AD, from Syria which at that
time was influenced by Christianity, tells about the magoi,
i.e. some Babylonian astronomers and astrologers, who by
observing a certain star (later called “the Bethlehem Star”) by
the mirroring water surface in a well in Northern Palestine,
were able to calculate and find a certain local direction. None
of these events would be understood by contemporaries, if this
practice was not well known.
One of the most respected Greek scholars, Eratosthenes (275-195
BC) calculated the circumference of the Earth by using the great
well to observe the lack of shadows by the sun's meridian
passage at summer solstice. This well from ancient pharaohnian
times is placed the Elephantine Island in the Nile at Syene
(Aswan) in Upper Egypt. The measuring of shadow angles was a
very old method in Egypt.
Eratosthenes’ arc measuring method: The shadow of the Pharos,
the famous Alexandrian
lighthouse, was c. 7 degrees of arc and was compared to
no-shadow at Syene’s well, from
where the exact vertical position of the sun was measured.
- and the Papyrus Rhind
The application of
geometrical calculations to the numbers in use by the astronomy
implies a highly sophisticated stage of mathematic-geometrical
skills by the ancient Egyptians. Indeed, this is confirmed by
the mathematical (and geometrical) Papyrus Rhind, c. 1650 BC.
Egyptian knowledge was famous - and at later times, Pythagoras
coined his theorem of the right-angled triangle c. 550 BC, after
having studied 22 years in Egypt. And Plato defined the Platonic
solids c. 400 BC, after 13 years in Egypt, according to his
The concept of pi was known in Ancient Egypt. Much later,
around 250 BC, Archimedes of Syracuse found that pi is
somewhere about 3.14 (in fractions, Greeks did not have
decimals). The digits of pi never end, nor has anyone
detected an orderly pattern in their arrangement. Furthermore,
pi is a transcendental number, i.e. a number which can't
be expressed in any finite series of either arithmetical or
algebraic operations. Pi transcends them. And pi
is indescribable and unfitted to all rational methods to locate
Moreover, a precise
knownledge of pi was existing even before the pyramids
more than 4,500 years ago. An important Egyptian measuring-unit
is the cubit, which has an exacte pi-relation to another
Egyptian measuring-unit, the remen. Here, 1 remen
constituates the radius of a cubit-square's circumscribed
circle. Thus, these two standard mesuring-units were more easy
and correct in use than calculating by fragments.
Papyrus Rhind demonstrating pyramid-angle calculation.
Written copy, 15 century BC, from older text.
We don’t know to what
extend this knowledge was conceived by the ancient Egyptians.
When pi was applied to the more practical works all the
conditions was not necessary to bring about. Earliest known
Egyptian written reference to pi occurs in the afore-mentioned
Papyrus Rhind, a scroll by the scribe Ahmesis of 15th Dynasty
reign (Middle Kingdom era) of the Hyksos Pharaoh, Apepi I.
(Found in Thebes/Luxor in the ruins of a small building near the
The advanced levels of studies by the ancients were connected to
the religious-mystical tradition, and the scroll’s opening words
state about its own text that it is: “The Entrance Into the
Knowledge of All Existing Things”.
The Rhind Papyrus
scroll consists of about 90 various mathematical problems and
their solutions. The 50th problem concerns the area of a circle
to be found by using - probably for practical reasons - a rough
sort of pi. Ahmesis remarks that he has composed the
scroll “in likeness to writings made of the ancients” - in this
case: the time of pharaoh Amenemhet III (1842-1797 BC). But
there exist several indications for the knowledge going much
further back in time, e.g. the 4th dynasty, 2500 BC, when
integrated into the construction of the pyramids and their
manifest star-positions-related orientation.
Ove von Spaeth
© 2000 & © 2004
independent researcher -
This text includes a number of extracts from “Den Hemmelige
Religion” (The Secret Religion)
- by Ove von Spaeth - which is volume No 4 in his series
( C.A. Reitzel, Publishers and Book Shop, phone (+45) 33 12 24
The Dendera Temple zodiac - a mixture of ancient Egyptian and
late Greek constellations.
Star map on the side of the water-clock’s container -
a clepsydra - from the time of Amenhotep I, c. 1550 BC.