Egyptian astronomy began in
prehistoric
Prehistory, also known as pre-literary history, is the period of human history between the use of the first stone tools by hominins 3.3 million years ago and the beginning of recorded history with the invention of writing systems. The use of ...
times, in the
Predynastic Period
Prehistoric Egypt and Predynastic Egypt span the period from the earliest human settlement to the beginning of the Early Dynastic Period around 3100 BC, starting with the first Pharaoh, Narmer for some Egyptologists, Hor-Aha for others, with ...
. In the 5th millennium BCE, the stone circles at
Nabta Playa
Nabta Playa was once a large Endorheic basin, internally drained basin in the Nubian Desert, located approximately 800 kilometers south of modern-day Cairo or about 100 kilometers west of Abu Simbel in southern Egypt, 22.51° north, 30.7 ...
may have made use of astronomical alignments. By the time the historical
Dynastic Period began in the 3rd millennium BCE, the 365 day period of the
Egyptian calendar was already in use, and the observation of
star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...
s was important in determining the annual flooding of the
Nile
The Nile, , Bohairic , lg, Kiira , Nobiin language, Nobiin: Áman Dawū is a major north-flowing river in northeastern Africa. It flows into the Mediterranean Sea. The Nile is the longest river in Africa and has historically been considered ...
.
The
Egyptian pyramids
The Egyptian pyramids are ancient masonry structures located in Egypt. Sources cite at least 118 identified "Egyptian" pyramids. Approximately 80 pyramids were built within the Kingdom of Kush, now located in the modern country of Sudan. Of ...
were carefully aligned towards the
pole star
A pole star or polar star is a star, preferably bright, nearly aligned with the axis of a rotating astronomical body.
Currently, Earth's pole stars are Polaris (Alpha Ursae Minoris), a bright magnitude-2 star aligned approximately with its ...
, and the temple of
Amun-Re
Amun (; also ''Amon'', ''Ammon'', ''Amen''; egy, jmn, reconstructed as (Old Egyptian and early Middle Egyptian) → (later Middle Egyptian) → (Late Egyptian), cop, Ⲁⲙⲟⲩⲛ, Amoun) romanized: ʾmn) was a major ancient Egyptian ...
at
Karnak
The Karnak Temple Complex, commonly known as Karnak (, which was originally derived from ar, خورنق ''Khurnaq'' "fortified village"), comprises a vast mix of decayed temples, pylons, chapels, and other buildings near Luxor, Egypt. Constr ...
was aligned on the rising of the
midwinter
Midwinter is the middle of the winter. The term is attested in the early Germanic calendars.
Attestations
Midwinter is attested in the early Germanic calendars, where it appears to have been a specific day or a number of days during the winter ha ...
Sun.
Astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
played a considerable part in fixing the dates of
religious festival
A religious festival is a time of special importance marked by adherents to that religion. Religious festivals are commonly celebrated on recurring cycles in a calendar year or lunar calendar. The science of religious rites and festivals is known ...
s and determining the hours of night, and temple
astrologers
Astrology is a range of divinatory practices, recognized as pseudoscientific since the 18th century, that claim to discern information about human affairs and terrestrial events by studying the apparent positions of celestial objects. Di ...
were especially adept at watching the stars and observing the
conjunctions and risings of the
Sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
,
Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
, and
planet
A planet is a large, rounded astronomical body that is neither a star nor its remnant. The best available theory of planet formation is the nebular hypothesis, which posits that an interstellar cloud collapses out of a nebula to create a you ...
s, as well as the
lunar phases.
In
Ptolemaic Egypt, the Egyptian tradition merged with
Greek astronomy
Greek astronomy is astronomy written in the Greek language in classical antiquity. Greek astronomy is understood to include the Ancient Greek, Hellenistic, Greco-Roman, and Late Antiquity eras. It is not limited geographically to Greece or to e ...
and
Babylonian astronomy
Babylonian astronomy was the study or recording of celestial objects during the early history of Mesopotamia.
Babylonian astronomy seemed to have focused on a select group of stars and constellations known as Ziqpu stars. These constellations ...
, with the city of
Alexandria
Alexandria ( or ; ar, ٱلْإِسْكَنْدَرِيَّةُ ; grc-gre, Αλεξάνδρεια, Alexándria) is the second largest city in Egypt, and the largest city on the Mediterranean coast. Founded in by Alexander the Great, Alexandria ...
in
Lower Egypt becoming the centre of scientific activity across the
Hellenistic world
In Classical antiquity, the Hellenistic period covers the time in Mediterranean history after Classical Greece, between the death of Alexander the Great in 323 BC and the emergence of the Roman Empire, as signified by the Battle of Actium in 3 ...
.
Roman Egypt produced the greatest astronomer of the era,
Ptolemy
Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importanc ...
(90–168 CE). His works on astronomy, including the
Almagest, became the most influential books in the history of Western astronomy. Following the
Muslim conquest of Egypt
The Muslim conquest of Egypt, led by the army of 'Amr ibn al-'As, took place between 639 and 646 AD and was overseen by the Rashidun Caliphate. It ended the seven-century-long period of Roman reign over Egypt that began in 30 BC. Byzantine ru ...
, the region came to be
dominated by Arabic culture and
Islamic astronomy
Islamic astronomy comprises the astronomical developments made in the Islamic world, particularly during the Islamic Golden Age (9th–13th centuries), and mostly written in the Arabic language. These developments mostly took place in the Middle ...
.
The astronomer
Ibn Yunus
Abu al-Hasan 'Ali ibn 'Abd al-Rahman ibn Ahmad ibn Yunus al-Sadafi al-Misri (Arabic: ابن يونس; c. 950 – 1009) was an important Egyptians, Egyptian astronomer and Islamic mathematics, mathematician, whose works are noted for being ahead o ...
(c. 950–1009) observed the
Sun's position for many years using a large
astrolabe, and his observations on
eclipses were still used centuries later. In 1006,
Ali ibn Ridwan
Abu'l Hassan Ali ibn Ridwan Al-Misri () (c. 988 - c. 1061) was an Arab of Egyptian origin who was a physician, astrologer and astronomer, born in Giza.
He was a commentator on ancient Greek medicine, and in particular on Galen; his commentary ...
observed the
SN 1006, a
supernova
A supernova is a powerful and luminous explosion of a star. It has the plural form supernovae or supernovas, and is abbreviated SN or SNe. This transient astronomical event occurs during the last evolutionary stages of a massive star or when ...
regarded as the brightest stellar event in
recorded history
Recorded history or written history describes the historical events that have been recorded in a written form or other documented communication which are subsequently evaluated by historians using the historical method. For broader world hist ...
, and left the most detailed description of it. In the 14th century, Najm al-Din al-Misri wrote a treatise describing over 100 different types of scientific and astronomical instruments, many of which he invented himself.
Ancient Egypt
Egyptian astronomy begins in prehistoric times. The presence of
stone circles
A stone circle is a ring of standing stones. Most are found in Northwestern Europe – especially in Britain, Ireland, and Brittany – and typically date from the Late Neolithic and Early Bronze Age, with most being built from 3000 BC. The b ...
at
Nabta Playa
Nabta Playa was once a large Endorheic basin, internally drained basin in the Nubian Desert, located approximately 800 kilometers south of modern-day Cairo or about 100 kilometers west of Abu Simbel in southern Egypt, 22.51° north, 30.7 ...
in
Upper Egypt
Upper Egypt ( ar, صعيد مصر ', shortened to , , locally: ; ) is the southern portion of Egypt and is composed of the lands on both sides of the Nile that extend upriver from Lower Egypt in the north to Nubia in the south.
In ancient E ...
dating from the
5th millennium BCE show the importance of
astronomy
Astronomy () is a natural science that studies astronomical object, celestial objects and phenomena. It uses mathematics, physics, and chemistry in order to explain their origin and chronology of the Universe, evolution. Objects of interest ...
to the religious life of
ancient Egypt even in the prehistoric period. The annual
flooding of the Nile
The flooding of the Nile has been an important natural cycle in Egypt since ancient times. It is celebrated by Egyptians as an annual holiday for two weeks starting August 15, known as ''Wafaa El-Nil''. It is also celebrated in the Coptic Church ...
meant that the
heliacal risings
The heliacal rising ( ) or star rise of a star occurs annually, or the similar phenomenon of a planet, when it first becomes visible above the eastern horizon at dawn just before sunrise (thus becoming "the Morning Star (disambiguation)#Astronomy, ...
, or first visible appearances of
star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...
s at
dawn
Dawn is the time that marks the beginning of twilight before sunrise. It is recognized by the appearance of indirect sunlight being scattered in Earth's atmosphere, when the centre of the Sun's disc has reached 18° below the observer's hori ...
, were of special interest in determining when this might occur, and it is no surprise that the 365 day period of the
Egyptian calendar was already in use at the beginning of
Egyptian history
The history of Egypt has been long and wealthy, due to the flow of the Nile River with its fertile banks and delta, as well as the accomplishments of Egypt's native inhabitants and outside influence. Much of Egypt's ancient history was a myste ...
. The
constellation
A constellation is an area on the celestial sphere in which a group of visible stars forms Asterism (astronomy), a perceived pattern or outline, typically representing an animal, mythological subject, or inanimate object.
The origins of the e ...
system used among the
Egyptians
Egyptians ( arz, المَصرِيُون, translit=al-Maṣriyyūn, ; arz, المَصرِيِين, translit=al-Maṣriyyīn, ; cop, ⲣⲉⲙⲛ̀ⲭⲏⲙⲓ, remenkhēmi) are an ethnic group native to the Nile, Nile Valley in Egypt. Egyptian ...
also appears to have been essentially of native origin. Archaeological evidence has linked fractal geometry designs among Sub-Saharan African cultures with Egyptian cosmological signs.
The precise orientation of the
Egyptian pyramid
The Egyptian pyramids are ancient masonry structures located in Egypt. Sources cite at least 118 identified "Egyptian" pyramids. Approximately 80 pyramids were built within the Kingdom of Kush, now located in the modern country of Sudan. Of ...
s serves as a lasting demonstration of the high degree of technical skill in watching the heavens attained in the
3rd millennium BCE. It has been shown the pyramids were aligned towards the
pole star
A pole star or polar star is a star, preferably bright, nearly aligned with the axis of a rotating astronomical body.
Currently, Earth's pole stars are Polaris (Alpha Ursae Minoris), a bright magnitude-2 star aligned approximately with its ...
, which, because of the
precession of the equinoxes
In astronomy, axial precession is a gravity-induced, slow, and continuous change in the orientation of an astronomical body's rotational axis. In the absence of precession, the astronomical body's orbit would show axial parallelism. In partic ...
, was at that time
Thuban
Thuban (), with Bayer designation Alpha Draconis or α Draconis, is a binary star system in the northern constellation of Draco. A relatively inconspicuous star in the night sky of the Northern Hemisphere, it is historically signi ...
, a faint star in the constellation of
Draco
Draco is the Latin word for serpent or dragon.
Draco or Drako may also refer to:
People
* Draco (lawgiver) (from Greek: Δράκων; 7th century BC), the first lawgiver of ancient Athens, Greece, from whom the term ''draconian'' is derived
* ...
. Evaluation of the site of the temple of
Amun-Re
Amun (; also ''Amon'', ''Ammon'', ''Amen''; egy, jmn, reconstructed as (Old Egyptian and early Middle Egyptian) → (later Middle Egyptian) → (Late Egyptian), cop, Ⲁⲙⲟⲩⲛ, Amoun) romanized: ʾmn) was a major ancient Egyptian ...
at
Karnak
The Karnak Temple Complex, commonly known as Karnak (, which was originally derived from ar, خورنق ''Khurnaq'' "fortified village"), comprises a vast mix of decayed temples, pylons, chapels, and other buildings near Luxor, Egypt. Constr ...
, taking into account the change over time of the
obliquity of the ecliptic
In astronomy, axial tilt, also known as obliquity, is the angle between an object's rotational axis and its orbital axis, which is the line perpendicular to its orbital plane; equivalently, it is the angle between its equatorial plane and o ...
, has shown that the Great Temple was aligned on the rising of the
midwinter
Midwinter is the middle of the winter. The term is attested in the early Germanic calendars.
Attestations
Midwinter is attested in the early Germanic calendars, where it appears to have been a specific day or a number of days during the winter ha ...
Sun. The length of the corridor down which sunlight would travel would have limited illumination at other times of the year.
Astronomy played a considerable part in
religious
Religion is usually defined as a social- cultural system of designated behaviors and practices, morals, beliefs, worldviews, texts, sanctified places, prophecies, ethics, or organizations, that generally relates humanity to supernatur ...
matters for fixing the dates of festivals and determining the hours of the
night
Night (also described as night time, unconventionally spelled as "nite") is the period of ambient darkness from sunset to sunrise during each 24-hour day, when the Sun is below the horizon. The exact time when night begins and ends depends o ...
. The titles of several temple books are preserved recording the movements and phases of the
Sun
The Sun is the star at the center of the Solar System. It is a nearly perfect ball of hot plasma, heated to incandescence by nuclear fusion reactions in its core. The Sun radiates this energy mainly as light, ultraviolet, and infrared radi ...
,
Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
and
star
A star is an astronomical object comprising a luminous spheroid of plasma (physics), plasma held together by its gravity. The List of nearest stars and brown dwarfs, nearest star to Earth is the Sun. Many other stars are visible to the naked ...
s. The rising of
Sirius
Sirius is the list of brightest stars, brightest star in the night sky. Its name is derived from the Ancient Greek language, Greek word , or , meaning 'glowing' or 'scorching'. The star is designated α Canis Majoris, Latinisation ...
(
Egyptian
Egyptian describes something of, from, or related to Egypt.
Egyptian or Egyptians may refer to:
Nations and ethnic groups
* Egyptians, a national group in North Africa
** Egyptian culture, a complex and stable culture with thousands of years of ...
:
Sopdet
Sopdet is the ancient Egyptian name of the star Sirius and its personification as an Egyptian goddess. Known to the Greeks as Sothis, she was conflated with Isis as a goddess and Anubis as a god.
Names
The exact pronunciation of ancien ...
,
Greek
Greek may refer to:
Greece
Anything of, from, or related to Greece, a country in Southern Europe:
*Greeks, an ethnic group.
*Greek language, a branch of the Indo-European language family.
**Proto-Greek language, the assumed last common ancestor ...
:
Sothis) at the beginning of the inundation was a particularly important point to fix in the yearly calendar.
One of the most important Egyptian astronomical texts was the
Book of Nut
The ''Book of Nut'' (original title: ''The Fundamentals of the Course of the Stars'') is a collection of ancient Egyptian astronomical texts, also covering various mythological subjects. These texts focus on the cycles of the stars of the decan ...
, going back to the
Middle Kingdom or earlier.
The death of a king had a strong connection to the stars for Ancient Egyptians. They believed once a king was deceased, their soul would rise to the heavens and become a star. The
Pyramid Texts
The Pyramid Texts are the oldest ancient Egyptian funerary texts, dating to the late Old Kingdom. They are the earliest known corpus of ancient Egyptian religious texts. Written in Old Egyptian, the pyramid texts were carved onto the subterrane ...
describe the king ascending and becoming the
Morning Star among the Imperishable Stars of past kings.
The First Intermediate Period
Beginning with the
9th Dynasty
The Ninth Dynasty of ancient Egypt (Dynasty IX) is often combined with the 7th, 8th, 10th and early 11th Dynasties under the group title First Intermediate Period.
The dynasty that seems to have supplanted the Eighth Dynasty is extremely obs ...
, ancient Egyptians produced 'Diagonal star tables', which were usually painted on the inside surface of wooden coffin lids. This practice continued until the
12th dynasty. These 'Diagonal star tables' or star charts are also known as 'diagonal star clocks'; in the past they have also been known as 'star calendars', or 'decanal clocks'. These star charts featuring the paintings of Egyptian deities,
decan
The decans (; Egyptian ''bꜣktw'' or ''baktiu'', "hoseconnected with work") are 36 groups of stars (small constellations) used in the ancient Egyptian astronomy to conveniently divide the 360 degree ecliptic into 36 parts of 10 degrees each, bo ...
s, constellations, and star observations are also found on the ceilings of tombs and temples.
From the tables of stars on the ceiling of the tombs of
Rameses VI and
Rameses IX
Neferkare Setepenre Ramesses IX (also written Ramses) (originally named Amon-her-khepshef Khaemwaset) (ruled 1129–1111 BC) was the eighth pharaoh of the Twentieth Dynasty of Egypt. He was the third longest serving king of this Dynasty after R ...
it seems that for fixing the hours of the night a man seated on the ground faced the Astrologer in such a position that the line of observation of the
pole star
A pole star or polar star is a star, preferably bright, nearly aligned with the axis of a rotating astronomical body.
Currently, Earth's pole stars are Polaris (Alpha Ursae Minoris), a bright magnitude-2 star aligned approximately with its ...
passed over the middle of his head. On the different days of the year each hour was determined by a fixed star
culminating or nearly culminating in it, and the position of these stars at the time is given in the tables as in the centre, on the left eye, on the right shoulder, etc. According to the texts, in founding or rebuilding temples the north axis was determined by the same apparatus, and we may conclude that it was the usual one for astronomical observations. In careful hands, it might give results of a high degree of accuracy.
[
]Macrobius Ambrosius Theodosius
Macrobius Ambrosius Theodosius, usually referred to as Macrobius (fl. AD 400), was a Roman provincial who lived during the early fifth century, during late antiquity, the period of time corresponding to the Later Roman Empire, and when Latin was ...
(''floruit'' 395–423 CE) attributed the planetary theory where the Earth rotates on its axis and the interior planets Mercury and Venus
Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never fa ...
revolve around the Sun
''Around the Sun'' is the 13th studio album by American alternative rock band R.E.M., released on October 5, 2004 on Warner Bros. Records.
Description
The album was released in three editions: Cassette (the band's final release on the medium), ...
which in turn revolves around the Earth, to the ancient Egyptians. He called it the "Egyptian System", and stated that "it did not escape the skill of the Egyptians
Egyptians ( arz, المَصرِيُون, translit=al-Maṣriyyūn, ; arz, المَصرِيِين, translit=al-Maṣriyyīn, ; cop, ⲣⲉⲙⲛ̀ⲭⲏⲙⲓ, remenkhēmi) are an ethnic group native to the Nile, Nile Valley in Egypt. Egyptian ...
", though there is no other evidence it was known in ancient Egypt.
Greco-Roman Egypt
Writing in the Roman era
In modern historiography, ancient Rome refers to Roman civilisation from the founding of the city of Rome in the 8th century BC to the collapse of the Western Roman Empire in the 5th century AD. It encompasses the Roman Kingdom (753–509 BC ...
, Clement of Alexandria
Titus Flavius Clemens, also known as Clement of Alexandria ( grc , Κλήμης ὁ Ἀλεξανδρεύς; – ), was a Christian theologian and philosopher who taught at the Catechetical School of Alexandria. Among his pupils were Origen and ...
gives some idea of the importance of astronomical observations to the sacred rites:
And after the Singer advances the Astrologer (ὡροσκόπος), with a ''horologium'' (ὡρολόγιον) in his hand, and a ''palm'' (φοίνιξ), the symbols of astrology. He must know by heart the Hermetic
Hermetic or related forms may refer to:
* of or related to the ancient Greek Olympian god Hermes
* of or related to Hermes Trismegistus, a legendary Hellenistic figure based on the Greek god Hermes and the Egyptian god Thoth
** , the ancient and m ...
astrological books, which are four in number. Of these, one is about the arrangement of the fixed stars that are visible; one on the positions of the sun and moon and five planets; one on the conjunctions and phases of the sun and moon; and one concerns their risings.
The astrologer's instruments (''horologium'' and ''palm'') are a plumb line
A plumb bob, plumb bob level, or plummet, is a weight, usually with a pointed tip on the bottom, suspended from a string and used as a vertical reference line, or plumb-line. It is a precursor to the spirit level and used to establish a vertic ...
and sighting instrument. They have been identified with two inscribed objects in the Berlin Museum; a short handle from which a plumb line was hung, and a palm branch with a sight-slit in the broader end. The palm branch was held close to the eye, the plumb line in the other hand – perhaps at arm's length.[
Following ]Alexander the Great
Alexander III of Macedon ( grc, wikt:Ἀλέξανδρος, Ἀλέξανδρος, Alexandros; 20/21 July 356 BC – 10/11 June 323 BC), commonly known as Alexander the Great, was a king of the Ancient Greece, ancient Greek kingdom of Maced ...
's conquests and the foundation of Ptolemaic Egypt, the native Egyptian tradition of astronomy had merged with Greek astronomy
Greek astronomy is astronomy written in the Greek language in classical antiquity. Greek astronomy is understood to include the Ancient Greek, Hellenistic, Greco-Roman, and Late Antiquity eras. It is not limited geographically to Greece or to e ...
as well as Babylonian astronomy
Babylonian astronomy was the study or recording of celestial objects during the early history of Mesopotamia.
Babylonian astronomy seemed to have focused on a select group of stars and constellations known as Ziqpu stars. These constellations ...
. The city of Alexandria
Alexandria ( or ; ar, ٱلْإِسْكَنْدَرِيَّةُ ; grc-gre, Αλεξάνδρεια, Alexándria) is the second largest city in Egypt, and the largest city on the Mediterranean coast. Founded in by Alexander the Great, Alexandria ...
in Lower Egypt became the centre of scientific activity throughout the Hellenistic civilization
In Classical antiquity, the Hellenistic period covers the time in Mediterranean history after Classical Greece, between the death of Alexander the Great in 323 BC and the emergence of the Roman Empire, as signified by the Battle of Actium in ...
. The greatest Alexandrian astronomer of this era was the Greek, Eratosthenes (c. 276–195 BCE), who calculated the size of the Earth
Earth is the third planet from the Sun and the only astronomical object known to harbor life. While large volumes of water can be found throughout the Solar System, only Earth sustains liquid surface water. About 71% of Earth's surfa ...
, providing an estimate for the circumference of the Earth.
Following the Roman conquest of Egypt, the region once again became the centre of scientific activity throughout the Roman Empire
The Roman Empire ( la, Imperium Romanum ; grc-gre, Βασιλεία τῶν Ῥωμαίων, Basileía tôn Rhōmaíōn) was the post-Republican period of ancient Rome. As a polity, it included large territorial holdings around the Mediterr ...
. The greatest astronomer of this era was the Hellenic Egyptian, Claudius Ptolemy
Claudius Ptolemy (; grc-gre, Πτολεμαῖος, ; la, Claudius Ptolemaeus; AD) was a mathematician, astronomer, astrologer, geographer, and music theorist, who wrote about a dozen scientific treatises, three of which were of importa ...
(90–168 CE). Originating from the Thebaid
The Thebaid or Thebais ( grc-gre, Θηβαΐς, ''Thēbaïs'') was a region in ancient Egypt, comprising the 13 southernmost nomes of Upper Egypt, from Abydos to Aswan.
Pharaonic history
The Thebaid acquired its name from its proximity to ...
region of Upper Egypt
Upper Egypt ( ar, صعيد مصر ', shortened to , , locally: ; ) is the southern portion of Egypt and is composed of the lands on both sides of the Nile that extend upriver from Lower Egypt in the north to Nubia in the south.
In ancient E ...
, he worked at Alexandria and wrote works on astronomy including the '' Almagest'', the ''Planetary Hypotheses'', and the ''Tetrabiblos
''Tetrabiblos'' () 'four books', also known in Greek as ''Apotelesmatiká'' () "Effects", and in Latin as ''Quadripartitum'' "Four Parts", is a text on the philosophy and practice of astrology, written in the 2nd century AD by the Alexandrian ...
'', as well as the ''Handy Tables'', the ''Canobic Inscription'', and other works unrelated to astronomy.
Ptolemy's '' Almagest'' (originally titled ''The Mathematical Syntaxis'') is one of the most influential books in the history of Western astronomy. In this book, Ptolemy explained how to predict the behavior of the planets with the introduction of a new mathematical idea, the equant
Equant (or punctum aequans) is a mathematical concept developed by Claudius Ptolemy in the 2nd century AD to account for the observed motion of the planets. The equant is used to explain the observed speed change in different stages of the plane ...
.
A few mathematicians of late Antiquity
Late antiquity is the time of transition from classical antiquity to the Middle Ages, generally spanning the 3rd–7th century in Europe and adjacent areas bordering the Mediterranean Basin. The popularization of this periodization in English ha ...
wrote commentaries on the ''Almagest'', including Pappus of Alexandria
Pappus of Alexandria (; grc-gre, Πάππος ὁ Ἀλεξανδρεύς; AD) was one of the last great Greek mathematicians of antiquity known for his ''Synagoge'' (Συναγωγή) or ''Collection'' (), and for Pappus's hexagon theorem i ...
as well as Theon of Alexandria
Theon of Alexandria (; grc, Θέων ὁ Ἀλεξανδρεύς; 335 – c. 405) was a Greek scholar and mathematician who lived in Alexandria, Egypt. He edited and arranged Euclid's '' Elements'' and wrote commentaries on wor ...
and his daughter Hypatia
Hypatia, Koine pronunciation (born 350–370; died 415 AD) was a neoplatonist philosopher, astronomer, and mathematician, who lived in Alexandria, Egypt, then part of the Eastern Roman Empire. She was a prominent thinker in Alexandria where ...
. Ptolemaic astronomy became standard in medieval western European and Islamic astronomy
Islamic astronomy comprises the astronomical developments made in the Islamic world, particularly during the Islamic Golden Age (9th–13th centuries), and mostly written in the Arabic language. These developments mostly took place in the Middle ...
until it was displaced by Maraghan, heliocentric, and Tychonic system
The Tychonic system (or Tychonian system) is a model of the Universe published by Tycho Brahe in the late 16th century, which combines what he saw as the mathematical benefits of the Copernican system with the philosophical and "physical" bene ...
s by the 16th century.
Islamic Egypt
Following the Muslim conquest of Egypt
The Muslim conquest of Egypt, led by the army of 'Amr ibn al-'As, took place between 639 and 646 AD and was overseen by the Rashidun Caliphate. It ended the seven-century-long period of Roman reign over Egypt that began in 30 BC. Byzantine ru ...
, the region came to be dominated by Arabic culture. It was ruled by the Rashidun, Umayyad
The Umayyad Caliphate (661–750 CE; , ; ar, ٱلْخِلَافَة ٱلْأُمَوِيَّة, al-Khilāfah al-ʾUmawīyah) was the second of the four major caliphates established after the death of Muhammad. The caliphate was ruled by the ...
and Abbasid Caliphate
The Abbasid Caliphate ( or ; ar, الْخِلَافَةُ الْعَبَّاسِيَّة, ') was the third caliphate to succeed the Islamic prophet Muhammad. It was founded by a dynasty descended from Muhammad's uncle, Abbas ibn Abdul-Muttalib ...
s up until the 10th century, when the Fatimids founded their own Caliphate
A caliphate or khilāfah ( ar, خِلَافَة, ) is an institution or public office under the leadership of an Islamic steward with the title of caliph (; ar, خَلِيفَة , ), a person considered a political-religious successor to th ...
centred around the city of Cairo
Cairo ( ; ar, القاهرة, al-Qāhirah, ) is the capital of Egypt and its largest city, home to 10 million people. It is also part of the largest urban agglomeration in Africa, the Arab world and the Middle East: The Greater Cairo metro ...
in Egypt. The region once again became a centre of scientific activity, competing with Baghdad
Baghdad (; ar, بَغْدَاد , ) is the capital of Iraq and the second-largest city in the Arab world after Cairo. It is located on the Tigris near the ruins of the ancient city of Babylon and the Sassanid Persian capital of Ctesiphon ...
for intellectual dominance in the medieval Islamic world. By the 13th century, the city of Cairo eventually overtook Baghdad as the intellectual center of the Islamic world.
Ibn Yunus
Abu al-Hasan 'Ali ibn 'Abd al-Rahman ibn Ahmad ibn Yunus al-Sadafi al-Misri (Arabic: ابن يونس; c. 950 – 1009) was an important Egyptians, Egyptian astronomer and Islamic mathematics, mathematician, whose works are noted for being ahead o ...
(c. 950–1009) observed more than 10,000 entries for the Sun's position for many years using a large astrolabe with a diameter of nearly 1.4 meters. His observations on eclipses were still used centuries later in Simon Newcomb
Simon Newcomb (March 12, 1835 – July 11, 1909) was a Canadian–American astronomer, applied mathematician, and autodidactic polymath. He served as Professor of Mathematics in the United States Navy and at Johns Hopkins University. Born in N ...
's investigations on the motion of the Moon, while his other observations inspired Laplace's ''Obliquity of the Ecliptic'' and ''Inequalities of Jupiter and Saturn''. [ ] In 1006, Ali ibn Ridwan
Abu'l Hassan Ali ibn Ridwan Al-Misri () (c. 988 - c. 1061) was an Arab of Egyptian origin who was a physician, astrologer and astronomer, born in Giza.
He was a commentator on ancient Greek medicine, and in particular on Galen; his commentary ...
observed the supernova of 1006, regarded as the brightest stellar event in recorded history, and left the most detailed description of the temporary star. He says that the object was two to three times as large as the disc of Venus
Venus is the second planet from the Sun. It is sometimes called Earth's "sister" or "twin" planet as it is almost as large and has a similar composition. As an interior planet to Earth, Venus (like Mercury) appears in Earth's sky never fa ...
and about one-quarter the brightness of the Moon
The Moon is Earth's only natural satellite. It is the fifth largest satellite in the Solar System and the largest and most massive relative to its parent planet, with a diameter about one-quarter that of Earth (comparable to the width of ...
, and that the star was low on the southern horizon.
The astrolabic quadrant was invented in Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
in the 11th century or 12th century, and later known in Europe as the " Quadrans Vetus" (Old Quadrant). In 14th century Egypt
Egypt ( ar, مصر , ), officially the Arab Republic of Egypt, is a transcontinental country spanning the northeast corner of Africa and southwest corner of Asia via a land bridge formed by the Sinai Peninsula. It is bordered by the Mediter ...
, Najm al-Din al-Misri (c. 1325) wrote a treatise describing over 100 different types of scientific and astronomical instruments, many of which he invented himself.
See also
* Ancient Egypt
* Archaeoastronomy
Archaeoastronomy (also spelled archeoastronomy) is the interdisciplinary or multidisciplinary study of how people in the past "have understood the phenomena in the sky, how they used these phenomena and what role the sky played in their cul ...
* Dendera zodiac
* Decans
The decans (; Egyptian ''bꜣktw'' or ''baktiu'', "hoseconnected with work") are 36 groups of stars (small constellations) used in the ancient Egyptian astronomy to conveniently divide the 360 degree ecliptic into 36 parts of 10 degrees each, bo ...
, Egyptian constellations.
* Egyptian astronomers
Egyptian describes something of, from, or related to Egypt.
Egyptian or Egyptians may refer to:
Nations and ethnic groups
* Egyptians, a national group in North Africa
** Egyptian culture, a complex and stable culture with thousands of years of ...
* Egyptian calendar
* Egyptian mathematics
* History of astronomy
** Babylonian astronomy
Babylonian astronomy was the study or recording of celestial objects during the early history of Mesopotamia.
Babylonian astronomy seemed to have focused on a select group of stars and constellations known as Ziqpu stars. These constellations ...
** Ancient Greek astronomy
Greek astronomy is astronomy written in the Greek language in classical antiquity. Greek astronomy is understood to include the Ancient Greek, Hellenistic, Greco-Roman, and Late Antiquity eras. It is not limited geographically to Greece or to e ...
** Medieval Islamic astronomy
* Nabta Playa
Nabta Playa was once a large Endorheic basin, internally drained basin in the Nubian Desert, located approximately 800 kilometers south of modern-day Cairo or about 100 kilometers west of Abu Simbel in southern Egypt, 22.51° north, 30.7 ...
* Sothic cycle
The Sothic cycle or Canicular period is a period of 1,461 Egyptian civil years of 365 days each or 1,460 Julian years averaging 365¼ days each. During a Sothic cycle, the 365-day year loses enough time that the start of its ...
Notes
References
Further reading
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External links
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