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Babylonian astronomy refers to the astronomy that developed in Mesopotamia, the "land between the rivers" Tigris and Euphrates, where the ancient kingdoms of Sumer, Assyria, Babylonia and Chaldea were located. Babylonian astronomy was the basis for much of the astronomical traditions that later developed in Indian astronomy, in Greek and Hellenistic astronomy, in Sassanid astronomy, in Byzantine and Syrian astronomy, in Islamic astronomy, and in Western European astronomy.^[1] Image File history File links Broom_icon. ... A giant Hubble mosaic of the Crab Nebula, a supernova remnant Astronomy (also frequently referred to as astrophysics) is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earths atmosphere (such as the cosmic background radiation). ... For other uses, see Mesopotamia (disambiguation). ... The Tigris is the eastern member of the pair of great rivers that define Mesopotamia, along with the Euphrates, which flows from the mountains of Anatolia through Iraq. ... Surfer Rosa The Euphrates (IPA: /juːˈfreɪtiːz/; Greek: EuphrátÄ“s; Akkadian: Pu-rat-tu; Hebrew: פְּרָת PÄ•rāth; Syriac: Prâth; Arabic: الفرات Al-Furāt; Turkish: Fırat; Kurdish: فرهات, Firhat, Ferhat, Azeri: FÉ™rat) is the western of the two great rivers that define Mesopotamia (the other... Sumer (or Å umer) was the earliest known civilization of the ancient Near East, located in lower Mesopotamia (modern Iraq) from the time of the earliest records in the mid 4th millennium BC until the rise of Babylonia in the late 3rd millennium BC. The term Sumerian applies to all speakers... In the Middle Bronze Age Assyria was a region on the Upper Tigris river, named for its original capital, the ancient city of Assur (Akkadian: ; Hebrew: , Aramaic: ). Later, as a nation and empire that came to control all of the Fertile Crescent, Egypt and much of Anatolia, the term Assyria... Babylonia was a state in the south part of Mesopotamia (in modern Iraq), combining the territories of Sumer and Akkad. ... For other uses, see Chaldean. ... The astronomy and the astrology of Ancient India (Jyotisha) is based upon sidereal calculations. ... A recreation of the famous Library of Alexandria Greek astronomy is the astronomy of those who spoke Greek in classical antiquity. ... After Islamic Conquest  Modern SSR = Soviet Socialist Republic Afghanistan  Azerbaijan  Bahrain  Iran  Iraq  Tajikistan  Uzbekistan  This box:      The Sassanid Empire or Sassanian Dynasty (Persian: []) is the name used for the fourth Iranian dynasty, and the second Persian Empire (226–651). ... Byzantine Empire at its greatest extent c. ... This is a sub-article of Islamic science and astronomy. ... The borders of Western Europe were largely defined by the Cold War. ...

The origins of Western astronomy can be found in Mesopotamia. A form of writing known as cuneiform emerged among the Sumerians around 3500-3000 BC. The Sumerians only practiced a basic form of astronomy, but they had an important influence on the sophisticated astronomy of the Babylonians. Astral theology, which gave planetary gods an important role in Mesopotamian mythology and religion, began with the Sumerians. They also used a sexagesimal (base 60) place-value number system, which simplified the task of recording very large and very small numbers. The modern practice of dividing a circle into 360 degrees, of 60 minutes each, began with the Sumerians. For more information, see the articles on Babylonian numerals and mathematics. Leonardo da Vincis Vitruvian Man, for many a symbol of the changes of the Western culture during the Renaissance Western culture or Western civilization is a term used to generally refer to most of the cultures of European origin and most of their descendants. ... Look up Cuneiform in Wiktionary, the free dictionary. ... Mesopotamian mythology is the collective name given to Sumerian, Akkadian, Assyrian, and Babylonian mythologies from the land between the Tigris and Euphrates rivers in Iraq. ... The sexagesimal (base-sixty) is a numeral system with sixty as the base. ... Babylonian numerals were written in cuneiform, using a wedge-tipped reed stylus to make a mark on a soft clay tablet which would be exposed in the sun to harden to create a permanent record. ... Babylonian mathematics refers to any mathematics of the peoples of Mesopotamia, from the days of the early Sumerians to the fall of Babylon in 539 BC. In contrast to the sparsity of sources in Egyptian mathematics, our knowledge of Babylonian mathematics is derived from some 400 clay tablets unearthed since...

Classical sources frequently use the term Chaldeans for the astronomers of Mesopotamia, who were, in reality, priest-scribes specializing in astrology and other forms of divination. Map showing the location of Tel Kaif, Iraq and the neighboring areas. ... Hand-coloured version of the anonymous Flammarion woodcut (1888). ... This article is about the religious practice of divination. ...

[edit] Old Babylonian astronomy

The first evidence of recognition that astronomical phenomena are periodic and of the application of mathematics to their prediction is Babylonian. Tablets dating back to the Old Babylonian period document the application of mathematics to the variation in the length of daylight over a solar year. Centuries of Babylonian observations of celestial phenomena are recorded in the series of cuneiform tablets known as the Enūma Anu Enlil. The oldest significant astronomical text that we possess is Tablet 63 of the Enūma Anu Enlil, the Venus tablet of Ammi-saduqa, which lists the first and last visible risings of Venus over a period of about 21 years and is the earliest evidence that the phenomena of a planet were recognized as periodic. The MUL.APIN, contains catalogues of stars and constellations as well as schemes for predicting heliacal risings and the settings of the planets, lengths of daylight measured by a water-clock, gnomon, shadows, and intercalations. The Babylonian GU text arranges stars in 'strings' that lie along declination circles and thus measure right-ascensions or time-intervals, and also employs the stars of the zenith, which are also separated by given right-ascensional differences.^[2] The chronology of the first dynasty of Babylonia is debated, because there is a Babylonian King List A and a Babylonian King List B. Hereby we follow temporarily the regnal years of List A, because those are widely used, although we believe that the other list is better, at least... Look up Cuneiform in Wiktionary, the free dictionary. ... Ammi-Saduqa (or Ammisaduqa, Ammizaduga) was a king of the First Dynasty of Babylon. ... MUL.APIN are ancient cuneiform tablets that were created around the 1400s BC to catalog the constellations of the day. ... The heliacal rising of a star (or other body such as the moon or a planet) occurs when it first becomes visible above the eastern horizon at dawn, after a period where it was hidden below the horizon or when it was just above the horizon but hidden by the... A water clock or clepsydra is a device for measuring time by letting water regularly flow out of a container, usually through a tiny aperture. ... The cantilever spar of this cable-stay bridge, the Sundial Bridge at Turtle Bay, forms the gnomon of a large garden sundial The gnomon is the part of a sundial that casts the shadow. ... Intercalation is the insertioffn of an extra day, week or month into some calendar years to make the calendar follow the seasons. ...

[edit] Neo-Babylonian astronomy

Neo-Babylonian astronomy refers to the astronomy developed by Chaldean astronomers during the Neo-Babylonian, Seleucid and Parthian periods of Mesopotamian history. A significant increase in the quality and frequency of Babylonian observations appeared during the reign of Nabonassar (747-733 BC), who founded the Neo-Babylonian Empire. The systematic records of ominous phenomena in astronomical diaries that began at this time allowed for the discovery of a repeating 18-year cycle of lunar eclipses, for example. The Egyptian astronomer Ptolemy later used Nabonassar's reign to fix the beginning of an era, since he felt that the earliest usable observations began at this time. For other uses, see Chaldean. ... Through the centuries of Assyrian domination, Babylonia enjoyed a prominent status, or revolting at the slightest indication that it did not. ... The Seleucid Empire was a Hellenistic successor state of Alexander the Greats dominion. ... Parthia[1] (Middle Persian: اشکانیان Ashkâniân) was a civilization situated in the northeast of modern Iran, but at its height covering all of Iran proper, as well as regions of the modern countries of Armenia, Iraq, Georgia, eastern Turkey, eastern Syria, Turkmenistan, Afghanistan, Tajikistan, Pakistan, Kuwait, the Persian Gulf... Nabonassar (also Nabonasser, Nabu-nasir, Nebo-adon-Assur or Nabo-n-assar) was a king of Assyria, who founded the Chaldean and Babylonian kingdom. ... Through the centuries of Assyrian domination, Babylonia enjoyed a prominent status, or revolting at the slightest indication that it did not. ... A medieval artists rendition of Claudius Ptolemaeus Claudius Ptolemaeus (Greek: ; ca. ...

The last stages in the development of Babylonian astronomy took place during the time of the Seleucid Empire (323-60 BC). In the third century BC, astronomers began to use "goal-year texts" to predict the motions of the planets. These texts compiled records of past observations to find repeating occurrences of ominous phenomena for each planet. About the same time, or shortly afterwards, astronomers created mathematical models that allowed them to predict these phenomena directly, without consulting past records. The Seleucid Empire was a Hellenistic successor state of Alexander the Greats dominion. ...

[edit] Empirical astronomy

Most of the Chaldean astronomers were concerned exclusively with ephemerides, and not with theory. The Babylonian planetary models were usually strictly empirical and arithmetical, and did not involve geometry, cosmology or philosophy like that of the Hellenistic models.^[3] An ephemeris (plural: ephemerides) (from the Greek word ephemeros = daily) is a device giving the positions of astronomical objects in the sky. ... In philosophy generally, empiricism is a theory of knowledge emphasizing the role of experience in the formation of ideas, while discounting the notion of innate ideas. ... Arithmetic tables for children, Lausanne, 1835 Arithmetic or arithmetics (from the Greek word αριθμός = number) is the oldest and most elementary branch of mathematics, used by almost everyone, for tasks ranging from simple daily counting to advanced science and business calculations. ... Calabi-Yau manifold Geometry (Greek γεωμετρία; geo = earth, metria = measure) is a part of mathematics concerned with questions of size, shape, and relative position of figures and with properties of space. ... Cosmology, from the Greek: κοσμολογία (cosmologia, κόσμος (cosmos) order + λογια (logia) discourse) is the study of the Universe in its totality, and by extension, humanitys place in it. ... The philosopher Socrates about to take poison hemlock as ordered by the court. ... A recreation of the famous Library of Alexandria Greek astronomy is the astronomy of those who spoke Greek in classical antiquity. ...

Chaldean astronomers known to have followed this model include Naburimannu (fl. 6th-3rd century BC), Kidinnu (d. 330 BC), Berossus (3rd century BC), and Sudines (fl. 240 BC). They are known to have had a significant influence on the Greek astronomer Hipparchus and the Egyptian astronomer Ptolemy, as well as other Hellenistic astronomers. Nabu-ri-man-nu (also spelled Nabu-rimanni; Greek sources called him Nabourianos, Latin Naburianus) (fl. ... Kidinnu (also Kidunnu) (circa 400 BC – possibly 14 August 330 BC) was a Chaldean astronomer and mathematician. ... This article cites its sources but does not provide page references. ... Sudines (Greek: Σουδινες) ca. ... A recreation of the famous Library of Alexandria Greek astronomy is the astronomy of those who spoke Greek in classical antiquity. ... For the Athenian tyrant, see Hipparchus (son of Pisistratus). ... A medieval artists rendition of Claudius Ptolemaeus Claudius Ptolemaeus (Greek: ; ca. ...

[edit] Heliocentric astronomy

Main article: Seleucus of Seleucia

The only Babylonian astronomer known to have supported a heliocentric model of planetary motion was Seleucus of Seleucia (b. 190 BC).^[4][5][6] Seleucus is known from the writings of Plutarch. He supported the heliocentric theory where the Earth rotated around its own axis which in turn revolved around the Sun. According to Plutarch, Seleucus even proved the heliocentric system, but it is not known what arguments he used. Seleucus (or Seleukos) of Seleucia (born circa 190 BC - ?) was a Greek philosopher. ... Heliocentric Solar System Heliocentrism (lower panel) in comparison to the geocentric model (upper panel) In astronomy, heliocentrism is the idea that the sun is at the center of the Universe and/or the Solar System. ... Seleucus (or Seleukos) of Seleucia (born circa 190 BC - ?) was a Greek philosopher. ... Centuries: 3rd century BC - 2nd century BC - 1st century BC Decades: 240s BC 230s BC 220s BC 210s BC 200s BC - 190s BC - 180s BC 170s BC 160s BC 150s BC 140s BC Years: 195 BC 194 BC 193 BC 192 BC 191 BC - 190 BC - 189 BC 188 BC... Mestrius Plutarchus (Greek: Πλούταρχος; 46 - 127), better known in English as Plutarch, was a Greek historian, biographer, essayist, and Middle Platonist. ... An animation showing the rotation of the Earth. ... The Sun (Latin: ) is the star at the center of the Solar System. ... Mestrius Plutarchus (Greek: Πλούταρχος; 46 - 127), better known in English as Plutarch, was a Greek historian, biographer, essayist, and Middle Platonist. ...

According to Lucio Russo, his arguments were probably related to the phenomenon of tides.^[7] Seleucus correctly theorized that tides were caused by the Moon, although he believed that the interaction was mediated by the Earth's atmosphere. He noted that the tides varied in time and strength in different parts of the world. According to Strabo (1.1.9), Seleucus was the first to state that the tides are due to the attraction of the Moon, and that the height of the tides depends on the Moon's position relative to the Sun.^[8] Lucio Russo (born 1944) is an Italian physicist, mathematician and historian of science. ... “Ebb tide” redirects here. ... “Ebb tide” redirects here. ... This article is about Earths moon. ... Layers of Atmosphere—not to scale (NOAA) [1] Earths atmosphere is a layer of gases surrounding the planet Earth and retained by the Earths gravity. ... The Greek geographer Strabo in a 16th century engraving. ... “Ebb tide” redirects here. ...

According to Bartel Leendert van der Waerden, Seleucus may have proved the heliocentric theory by determining the constants of a geometric model for the heliocentric theory and by developing methods to compute planetary positions using this model. He may have used trigonometric methods that were available in his time, as he was a contemporary of Hipparchus.^[9] Bartel Leendert van der Waerden (February 2, 1903, Amsterdam, Netherlands – January 12, 1996, Zürich, Switzerland) was a Dutch mathematician. ... Calabi-Yau manifold Geometry (Greek γεωμετρία; geo = earth, metria = measure) is a part of mathematics concerned with questions of size, shape, and relative position of figures and with properties of space. ... Wikibooks has a book on the topic of Trigonometry All of the trigonometric functions of an angle θ can be constructed geometrically in terms of a unit circle centered at O. Trigonometry (from Greek trigōnon triangle + metron measure[1]), informally called trig, is a branch of mathematics that deals with... For the Athenian tyrant, see Hipparchus (son of Pisistratus). ...

[edit] Babylonian influence on Hellenistic astronomy

Many of the works of ancient Greek and Hellenistic writers (including mathematicians, astronomers, and geographers) have been preserved up to the present time, or some aspects of their work and thought are still known through later references. However, achievements in these fields by earlier ancient Near Eastern civilizations, notably those in Babylonia, were forgotten for a long time. Since the discovery of key archaeological sites in the 19th century, many cuneiform writings on clay tablets have been found, some of them related to astronomy. Most known astronomical tablets have been described by Abraham Sachs and later published by Otto Neugebauer in the Astronomical Cuneiform Texts (ACT). The term Hellenistic (derived from Héllēn, the Greeks traditional self-described ethnic name) was established by the German historian Johann Gustav Droysen to refer to the spreading of Greek culture over the non-Greek people that were conquered by Alexander the Great. ... Greek mathematics, as that term is used in this article, is the mathematics written in Greek, developed from the 6th century BC to the 5th century AD around the Eastern shores of the Mediterranean. ... A recreation of the famous Library of Alexandria Greek astronomy is the astronomy of those who spoke Greek in classical antiquity. ... A geographer is a scientist whose area of study is geography, the study of the physical environment and human habitat. ... Overview map of the Ancient Near East The term Ancient Near East or Ancient Orient encompasses the early civilizations predating Classical Antiquity in the region roughly corresponding to that described by the modern term Middle East (Egypt, Iraq, Turkey), during the time roughly spanning the Bronze Age from the rise... Babylonia was a state in the south part of Mesopotamia (in modern Iraq), combining the territories of Sumer and Akkad. ... The cuneiform script is one of the earliest known forms of written expression. ... Small tablets made out of clay were used from late 4th millennium BC onwards as a writing medium in Sumerian, Mesopotamian, Hittite, and Minoan/Mycenaean civilizations. ... A giant Hubble mosaic of the Crab Nebula, a supernova remnant Astronomy (also frequently referred to as astrophysics) is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earths atmosphere (such as the cosmic background radiation). ...

Since the rediscovery of the Babylonian civilization, it has become apparent that Hellenistic astronomy was strongly influenced by the Chaldeans. The best documented borrowings are those of Hipparchus (2nd century BCE) and Claudius Ptolemy (2nd century CE). A recreation of the famous Library of Alexandria Greek astronomy is the astronomy of those who spoke Greek in classical antiquity. ... For other uses, see Chaldean. ... For the Athenian tyrant, see Hipparchus (son of Pisistratus). ... A medieval artists rendition of Claudius Ptolemaeus Claudius Ptolemaeus (Greek: ; ca. ...

[edit] Early influence

Many scholars agree that the Metonic cycle is likely to have been learned by the Greeks from Babylonian scribes. Meton of Athens, a Greek astronomer of the 5th century BCE, developed a lunisolar calendar based on the fact that 19 solar years is about equal to 235 lunar months, a period relation already known to the Babylonians. The Metonic cycle or Enneadecaeteris in astronomy and calendar studies is a particular approximate common multiple of the year (specifically, the seasonal tropical year) and the synodic month. ... Meton of Athens was a Greek mathematician, astronomer, geometer, and engineer who lived in Athens in the 5th century BCE. He is best known for the 19-year Metonic cycle which he introduced in 432 BCE into the lunisolar Attic calendar as a method of calculating dates. ... A lunisolar calendar is a calendar whose date indicates both the moon phase and the time of the solar year. ...

In the fourth century, Eudoxus of Cnidus wrote a book on the fixed stars. His descriptions of many constellations, especially the twelve signs of the zodiac, are suspiciously similar to Babylonian originals. The following century Aristarchus of Samos used an eclipse cycle of Babylonian origin called the Saros cycle to determine the year length. However, all these examples of early influence must be inferred and the chain of transmission is not known. Eudoxus of Cnidus was the son of Aischines. ... A fixed star is a celestial object that does not seem to move (in comparison to the other stars of the night sky). ... The term zodiac denotes an annual cycle of twelve stations along the ecliptic, the apparent path of the sun across the heavens through constellations that divide the ecliptic into twelve equal zones of celestial longitude. ... Statue of Aristarchus at Aristotle University in Thessalonica, Greece Aristarchus (Greek: Ἀρίσταρχος; 310 BC - ca. ... A Saros cycle is a period of 6585 + 1/3 days (approximately 18 years 10 days and 8 hours) which can be used to predict eclipses of the sun and the moon. ...

[edit] Influence on Hipparchus and Ptolemy

In 1900, Franz Xaver Kugler demonstrated that Ptolemy had stated in his Almagest IV.2 that Hipparchus improved the values for the Moon's periods known to him from "even more ancient astronomers" by comparing eclipse observations made earlier by "the Chaldeans", and by himself. However Kugler found that the periods that Ptolemy attributes to Hipparchus had already been used in Babylonian ephemerides, specifically the collection of texts nowadays called "System B" (sometimes attributed to Kidinnu). Apparently Hipparchus only confirmed the validity of the periods he learned from the Chaldeans by his newer observations. Later Greek knowledge of this specific Babylonian theory is confirmed by second-century papyrus, which contains 32 lines of a single column of calculations for the Moon using this same "System B", but written in Greek on papyrus rather than in cuneiform on clay tablets.^[10] Almagest is the Latin form of the Arabic name (al-kitabu-l-mijisti, i. ... An ephemeris (plural: ephemerides) (from the Greek word ephemeros= daily) was, traditionally, a table providing the positions (given in a Cartesian coordinate system, or in right ascension and declination or, for astrologers, in longitude along the zodiacal ecliptic), of the Sun, the Moon, and the planets in the sky at... Kidinnu (also Kidunnu) (circa 400 BC – possibly 14 August 330 BC) was a Chaldean astronomer and mathematician. ...

It is clear that Hipparchus (and Ptolemy after him) had an essentially complete list of eclipse observations covering many centuries. Most likely these had been compiled from the "diary" tablets: these are clay tablets recording all relevant observations that the Chaldeans routinely made. Preserved examples date from 652 BC to AD 130, but probably the records went back as far as the reign of the Babylonian king Nabonassar: Ptolemy starts his chronology with the first day in the Egyptian calendar of the first year of Nabonassar, i.e., 26 February, 747 BC. Centuries: 8th century BC - 7th century BC - 6th century BC Decades: 700s BC 690s BC 680s BC 670s BC 660s BC - 650s BC - 640s BC 630s BC 620s BC 610s BC 600s BC Events and Trends Occupation begins at Maya site of Piedras Negras, Guatemala 657 BC - Cypselus becomes the... For other uses, see number 130. ... Nabonassar (also Nabonasser, Nabu-nasir, Nebo-adon-Assur or Nabo-n-assar) was a king of Assyria, who founded the Chaldean and Babylonian kingdom. ... Centuries: 9th century BC - 8th century BC - 7th century BC Decades: 790s BC 780s BC 770s BC 760s BC 750s BC - 740s BC - 730s BC 720s BC 710s BC 700s BC 690s BC Events and Trends February 26 747 BC - Nabonassar becomes king of Assyria 747 BC - Meles becomes king...

This raw material by itself must have been hard to use, and no doubt the Chaldeans themselves compiled extracts of e.g., all observed eclipses (some tablets with a list of all eclipses in a period of time covering a saros have been found). This allowed them to recognise periodic recurrences of events. Among others they used in System B (cf. Almagest IV.2): A Saros cycle is a period of 6585 + 1/3 days (approximately 18 years 10 days and 8 hours) which can be used to predict eclipses of the sun and the moon. ...

• 223 (synodic) months = 239 returns in anomaly (anomalistic month) = 242 returns in latitude (draconic month). This is now known as the saros period which is very useful for predicting eclipses.
• 251 (synodic) months = 269 returns in anomaly
• 5458 (synodic) months = 5923 returns in latitude
• 1 synodic month = 29;31:50:08:20 days (sexagesimal; 29.53059413... days in decimals = 29 days 12 hours 44 min 3⅓ s)

The Babylonians expressed all periods in synodic months, probably because they used a lunisolar calendar. Various relations with yearly phenomena led to different values for the length of the year. The orbital period is the time it takes a planet (or another object) to make one full orbit. ... In Egyptian mythology, Month is an alternate spelling for Menthu. ... In Egyptian mythology, Month is an alternate spelling for Menthu. ... A Saros cycle is a period of 6585 + 1/3 days (approximately 18 years 10 days and 8 hours) which can be used to predict eclipses of the sun and the moon. ... This article is about astronomical eclipses. ... In Egyptian mythology, Month is an alternate spelling for Menthu. ... Look up Month in Wiktionary, the free dictionary. ... A lunisolar calendar is a calendar whose date indicates both the moon phase and the time of the solar year. ...

Similarly various relations between the periods of the planets were known. The relations that Ptolemy attributes to Hipparchus in Almagest IX.3 had all already been used in predictions found on Babylonian clay tablets. The eight planets and three dwarf planets of the Solar System. ...

Other traces of Babylonian practice in Hipparchus' work are:

• first Greek known to divide the circle in 360 degrees of 60 arc minutes.
• first consistent use of the sexagesimal number system.
• the use of the unit pechus ("cubit") of about 2° or 2½°.
• use of a short period of 248 days = 9 anomalistic months.

This article describes the unit of angle. ... A minute of arc, arcminute, or MOA is a unit of angular measurement, equal to one sixtieth (1/60) of one degree. ... The sexagesimal (base-sixty) is a numeral system with sixty as the base. ...

[edit] Means of transmission

All this knowledge was transferred to the Greeks probably shortly after the conquest by Alexander the Great (331 BC). According to the late classical philosopher Simplicius (early 6th century AD), Alexander ordered the translation of the historical astronomical records under supervision of his chronicler Callisthenes of Olynthus, who sent it to his uncle Aristotle. It is worth mentioning here that although Simplicius is a very late source, his account may be reliable. He spent some time in exile at the Sassanid (Persian) court, and may have accessed sources otherwise lost in the West. It is striking that he mentions the title tèresis (Greek: guard) which is an odd name for a historical work, but is in fact an adequate translation of the Babylonian title massartu meaning "guarding" but also "observing". Anyway, Aristotle's pupil Callippus of Cyzicus introduced his 76-year cycle, which improved upon the 19-year Metonic cycle, about that time. He had the first year of his first cycle start at the summer solstice of 28 June 330 BC (Julian proleptic date), but later he seems to have counted lunar months from the first month after Alexander's decisive battle at Gaugamela in fall 331 BC. So Callippus may have obtained his data from Babylonian sources and his calendar may have been anticipated by Kidinnu. Also it is known that the Babylonian priest known as Berossus wrote around 281 BC a book in Greek on the (rather mythological) history of Babylonia, the Babyloniaca, for the new ruler Antiochus I; it is said that later he founded a school of astrology on the Greek island of Kos. Another candidate for teaching the Greeks about Babylonian astronomy/astrology was Sudines who was at the court of Attalus I Soter late in the 3rd century BC. For the film of the same name, see Alexander the Great (1956 film). ... Centuries: 5th century BC - 4th century BC - 3rd century BC Decades: 380s BC 370s BC 360s BC 350s BC 340s BC - 330s BC - 320s BC 310s BC 300s BC 290s BC 280s BC Years: 336 BC 335 BC 334 BC 333 BC 332 BC - 331 BC - 330 BC 329 BC... Simplicius, a native of Cilicia, a disciple of Ammonius and of Damascius, was one of the last of the Neoplatonists. ... (5th century — 6th century — 7th century — other centuries) Events The first academy of the east the Academy of Gundeshapur founded in Persia by the Persian Shah Khosrau I. Irish colonists and invaders, the Scots, began migrating to Caledonia (later known as Scotland) Glendalough monastery, Wicklow Ireland founded... Callisthenes, or Kallisthenes, ( in Greek) of Olynthus (c. ... Aristotle (Greek: AristotélÄ“s) (384 BC – 322 BC) was a Greek philosopher, a student of Plato and teacher of Alexander the Great. ... Sassanid Empire at its greatest extent The Sassanid dynasty (also Sassanian) was the name given to the kings of Persia during the era of the second Persian Empire, from 224 until 651, when the last Sassanid shah, Yazdegerd III, lost a 14-year struggle to drive out the Umayyad Caliphate... Calippus of Syracuse Callippus (or Calippus) (ca. ... The Metonic cycle or Enneadecaeteris in astronomy and calendar studies is a particular approximate common multiple of the year (specifically, the seasonal tropical year) and the synodic month. ... is the 179th day of the year (180th in leap years) in the Gregorian calendar. ... Centuries: 5th century BC - 4th century BC - 3rd century BC Decades: 380s BC 370s BC 360s BC 350s BC 340s BC - 330s BC - 320s BC 310s BC 300s BC 290s BC 280s BC 335 BC 334 BC 333 BC 332 BC 331 BC - 330 BC - 329 BC 328 BC 327... The Julian calendar was introduced in 46 BC by Julius Caesar and came into force in 45 BC (709 ab urbe condita). ... A Proleptic calendar or era is that calendar extrapolated to dates prior the its first adoption. ... In the Battle of Gaugamela in 331 BC Alexander the Great of Macedonia defeated Darius III of Persia. ... Centuries: 5th century BC - 4th century BC - 3rd century BC Decades: 380s BC 370s BC 360s BC 350s BC 340s BC - 330s BC - 320s BC 310s BC 300s BC 290s BC 280s BC Years: 336 BC 335 BC 334 BC 333 BC 332 BC - 331 BC - 330 BC 329 BC... This article cites its sources but does not provide page references. ... Centuries: 4th century BC - 3rd century BC - 2nd century BC Decades: 330s BC 320s BC 310s BC 300s BC 290s BC - 280s BC - 270s BC 260s BC 250s BC 240s BC 230s BC 286 BC 285 BC 284 BC 283 BC 282 BC 281 BC 280 BC 279 BC 278... Silver coin of Antiochus I Antiochus I Soter ( 324/323_262/261 BC reigned 281 BC - 261 BC) was half Persian, his mother Apame being one of those eastern princesses whom Alexander had given as wives to his generals in 324 BC. On the assassination of his father Seleucus I in... Hand-coloured version of the anonymous Flammarion woodcut (1888). ... Port and city view of Kos town on the island Kos. ... A giant Hubble mosaic of the Crab Nebula, a supernova remnant Astronomy (also frequently referred to as astrophysics) is the scientific study of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earths atmosphere (such as the cosmic background radiation). ... Hand-coloured version of the anonymous Flammarion woodcut (1888). ... Sudines (Greek: Σουδινες) ca. ... Bust of Attalus I, circa 200 BCE (Pergamon Museum, Berlin) Attalus I Soter (Greek: Savior; 269 BC – 197 BC)[1] ruled Pergamon, a Greek polis in what is now Turkey, from 241 BC to 197 BC. He was the second cousin and the adoptive son of Eumenes I,[2] whom... The 3rd century BC started the first day of 300 BC and ended the last day of 201 BC. It is considered part of the Classical era, epoch, or historical period. ...

In any case, the translation of the astronomical records required profound knowledge of the cuneiform script, the language, and the procedures, so it seems likely that it was done by some unidentified Chaldeans. Now, the Babylonians dated their observations in their lunisolar calendar, in which months and years have varying lengths (29 or 30 days; 12 or 13 months respectively). At the time they did not use a regular calendar (such as based on the Metonic cycle like they did later), but started a new month based on observations of the New Moon. This made it very tedious to compute the time interval between events. The cuneiform script is one of the earliest known forms of written expression. ... The Metonic cycle or Enneadecaeteris in astronomy and calendar studies is a particular approximate common multiple of the year (specifically, the seasonal tropical year) and the synodic month. ... The lunar phase depends on the Moons position in orbit around Earth. ...

What Hipparchus may have done is transform these records to the Egyptian calendar, which uses a fixed year of always 365 days (consisting of 12 months of 30 days and 5 extra days): this makes computing time intervals much easier. Ptolemy dated all observations in this calendar. He also writes that "All that he (=Hipparchus) did was to make a compilation of the planetary observations arranged in a more useful way" (Almagest IX.2). Pliny states (Naturalis Historia II.IX(53)) on eclipse predictions: "After their time (=Thales) the courses of both stars (=Sun and Moon) for 600 years were prophesied by Hipparchus, ...". This seems to imply that Hipparchus predicted eclipses for a period of 600 years, but considering the enormous amount of computation required, this is very unlikely. Rather, Hipparchus would have made a list of all eclipses from Nabonasser's time to his own. The ancient civil Egyptian Calendar, known as the Annus Vagus or Wandering Year, had a year that was 365 days long, consisting of 12 months of 30 days each, plus 5 extra days at the end of the year. ... Thales of Miletos (, ca. ...

[edit] Notes

George Alfred Leon Sarton (1884-1956) was a seminal Belgian-American polymath and historian of science. ... Otto E. Neugebauer (May 26, 1899 – February 19, 1990) was an Austrian-American mathematician and historian of science who became known for his research on the history of astronomy and the other exact (i. ... George Alfred Leon Sarton (1884-1956) was a seminal Belgian-American polymath and historian of science. ... Lucio Russo (born 1944) is an Italian physicist, mathematician and historian of science. ... Bartel Leendert van der Waerden (February 2, 1903, Amsterdam, Netherlands – January 12, 1996, Zürich, Switzerland) was a Dutch mathematician. ... Bartel Leendert van der Waerden (February 2, 1903, Amsterdam, Netherlands – January 12, 1996, Zürich, Switzerland) was a Dutch mathematician. ...

[edit] References

• Aaboe, Asger. Episodes from the Early History of Astronomy. New York: Springer, 2001. ISBN 0-387-95136-9
• Jones, Alexander. "The Adaptation of Babylonian Methods in Greek Numerical Astronomy." Isis, 82(1991): 441-453; reprinted in Michael Shank, ed. The Scientific Enterprise in Antiquity and the Middle Ages. Chicago: Univ. of Chicago Pr., 2000. ISBN 0-226-74951-7
• Kugler, F. X. Die Babylonische Mondrechnung ("The Babylonian lunar computation.") Freiburg im Breisgau, 1900.
• Neugebauer, Otto. Astronomical Cuneiform Texts. 3 volumes. London:1956; 2nd edition, New York: Springer, 1983. (Commonly abbreviated as ACT).
• Toomer, G. J. "Hipparchus and Babylonian Astronomy." In A Scientific Humanist: Studies in Memory of Abraham Sachs, ed. Erle Leichty, Maria deJ. Ellis, and Pamela Gerardi, pp. 353-362. Philadelphia: Occasional Publications of the Samuel Noah Kramer Fund 9, 1988.

[edit] See also

• Babylonian astrology
• Babylonian calendar
• History of astronomy (Section on Mesopotamia)