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Encyclopedia > Greek astronomy
A recreation of the famous Library of Alexandria

Greek astronomy is the astronomy of those who spoke Greek in classical antiquity. It is understood to include the ancient Greek, Hellenistic, Greco-Roman, and Late Antiquity eras. It is not limited geographically to Greece or to ethnic Greeks, as the Greek language had become the language of scholarship throughout the Hellenistic world following the conquests of Alexander. This phase of Greek astronomy is also known as Hellenistic astronomy, while the pre-Hellenistic phase is known as Classical Greek astronomy. During the Hellenistic and Roman periods, much of the Greek and non-Greek astronomers working in the Greek tradition studied at the Musaeum and the Library of Alexandria in Ptolemaic Egypt. (The reconstruction of the Musaeum, shown right, was designed for Carl Sagan's television show Cosmos in 1980.) The development of astronomy by the Greek and Hellenistic astronomers is considered by historians to be a major phase in the history of astronomy in Western culture. It depended heavily on Babylonian astronomy; in turn, it influenced Islamic astronomy, and medieval and Renaissance European astronomy. Reconstruction of the Museum of Alexandria, with doors leading to the rooms of the Library. ... Reconstruction of the Museum of Alexandria, with doors leading to the rooms of the Library. ... A giant Hubble mosaic of the Crab Nebula, a supernova remnant Astronomy is the science of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earths atmosphere (such as auroras and cosmic background radiation). ... Classical antiquity is a broad term for a long period of cultural history centered on the Mediterranean Sea, which begins roughly with the earliest-recorded Greek poetry of Homer (7th century BC), and continues through the rise of Christianity and the fall of the Western Roman Empire (5th century AD... The Temple to Athena, the Parthenon Ancient Greece is a period in Greek history that lasted for around three thousand years. ... 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. ... In modern Olympic and amateur wrestling, Greco-Roman wrestling is a particular style and variation. ... Late Antiquity is a rough periodization (c. ... Physical map of the Earth (Medium) (Large 2 MB) Geography is the scientific study of the locational and spatial variation in both physical and human phenomena on Earth. ... 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 peoples that were conquered by Alexander the Great. ... For other uses, see Alexander (disambiguation). ... An astronomer or astrophysicist is a scientist whose area of research is astronomy or astrophysics. ... The original Musaeum or Temple of the Muses at ancient Alexandria was the source for the modern usage, which denoted in Early Modern France as much a community of scholars brought together under one roof as it did the collections themselves, which French and English writers referred to as a... Inscription regarding Tiberius Claudius Balbilus of Rome (d. ... The Ptolemaic dynasty in Egypt began following Alexander the Greats conquest in 332 BC and ended with the death of Cleopatra VII and the Roman conquest in 30 BC. It was founded when Ptolemy I Soter declared himself Pharaoh of Egypt, creating a powerful Hellenistic state from southern Syria... Insert non-formatted text here Carl Edward Sagan (November 9, 1934 – December 20, 1996) was an American astronomer and astrobiologist and a highly successful popularizer of astronomy, astrophysics, and other natural sciences. ... Cosmos: A Personal Voyage was the name of a thirteen part television series produced by Carl Sagan and Ann Druyan which was first broadcast by the Public Broadcasting Service in 1980. ... Astronomy is probably the oldest of the natural sciences, dating back to antiquity, with its origins in the religious practices of pre-history: vestiges of these are still found in astrology, a discipline long interwoven with astronomy, and not completely different from it until about 1750‑1800 in the Western... It has been suggested that this article or section be merged with Western World. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... This is a sub-article of Islamic science and astronomy. ... The Middle Ages formed the middle period in a traditional schematic division of European history into three ages: the classical civilization of Antiquity, the Middle Ages, and modern times, beginning with the Renaissance. ... The Renaissance (French for rebirth, or Rinascimento in Italian), was a cultural movement in Italy (and in Europe in general) that began in the late Middle Ages, and spanned roughly the 14th through the 17th century. ... World map showing the location of Europe. ...

Contents

Archaic Greek astronomy

References to identifiable stars and constellations appear in the writings of Homer and Hesiod, the earliest surviving examples of Greek literature. In the Iliad and the Odyssey, Homer refers to the following celestial objects: For alternate meanings see star (disambiguation) Hundreds of stars are visible in this image taken by the Hubble Space Telescope of the Sagittarius Star Cloud in the Milky Way Galaxy. ... This article or section does not adequately cite its references or sources. ... Homer (Greek: , ) was an early Greek poet and aoidos (rhapsode) traditionally credited with the composition of the Iliad and the Odyssey. ... Roman bronze bust, the so-called Pseudo-Seneca, now identified by some as possibly Hesiod Hesiod (Hesiodos, ) was an early Greek poet and rhapsode, who presumably lived around 700 BC. Hesiod and Homer, with whom Hesiod is often paired, have been considered the earliest Greek poets whose work has survived... It has been suggested that Deception of Zeus be merged into this article or section. ... Beginning of the Odyssey The Odyssey (Greek Οδύσσεια (Odússeia) ) is one of the two major ancient Greek epic poems attributed to the Ionian poet Homer. ...

Hesiod, who wrote in the early 7th century BCE, adds the star Arcturus to this list in his poetic calendar Works and Days. Though neither Homer nor Hesiod set out to write a scientific work, they hint at a rudimentary cosmology of a flat earth surrounded by an "Ocean River." Some stars rise and set (disappear into the ocean, from the viewpoint of the Greeks); others are ever-visible. At certain times of the year, certain stars will rise or set at sunrise or sunset. Boötes (IPA: ), a name deriving from Egypt, is one of the 88 modern constellations and was also one of the 48 constellations listed by Ptolemy. ... This article or section does not cite its references or sources. ... The Hyades (ÆΥάδες also known as Melotte 25 or Collinder 50 or Caldwell 41) is an open star cluster located in the constellation Taurus. ... Orion (IPA: ), a constellation often referred to as The Hunter, is a prominent constellation, one of the largest and perhaps the best-known and most conspicuous in the sky. ... A shorter exposure shows less nebulosity. ... For information on Sirius satellite radio, see Sirius Satellite Radio. ... Ursa Major (IPA: ) is a constellation visible throughout the year in most of the northern hemisphere. ... Arcturus (α Boo / α Boötis / Alpha Boötis) (IPA: ) is the brightest star in the constellation Boötes, and the third brightest star in the night sky, with a visual magnitude of −0. ... 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. ... 15th century adaptation of a T-O map. ... In the Greek and Roman world-view, Oceanus (Greek , Okeanos), was the world-ocean, which they believed to be an enormous river encircling the world. ... In astronomy, circumpolar constellations are those that, from the viewers latitude, never set. ...

Anaximander
Anaximander

Speculation about the cosmos was common in Pre-Socratic philosophy in the 6th and 5th centuries BCE. Anaximander (c.610 BC–c. 546 BC) described a cylindrical earth suspended in the center of the cosmos, surrounded by rings of fire. Philolaus (c. 480 BC–c. 405 BC) the Pythagorean described a cosmos with the stars, planets, Sun, Moon, Earth, and a counter-Earth (Antichthon)--ten bodies in all--circling an unseen central fire. Such reports show that Greeks of the 6th and 5th centuries were aware of the planets and speculated about the structure of the cosmos. Image File history File links Anaximander. ... Image File history File links Anaximander. ... The Ancient and Medieval cosmos as depicted in Peter Apians Cosmographia (Antwerp, 1539). ... The Pre-Socratic philosophers were active before Socrates or contemporaneously, but expounding knowledge developed earlier. ... Anaximander Possibly what Anaximanders map looked like Anaximander (Greek: Αναξίμανδρος)(c. ... Philolaus (circa 480 BC – circa 405 BC) was a Greek mathematician and philosopher. ... Bust of Pythagoras Pythagoreanism is a term used for the esoteric and metaphysical beliefs held by Pythagoras and his followers, the Pythagoreans, who were much influenced by mathematics and probably a main inspirational source for Plato and platonism. ... The Sun is the star at the center of the Solar System. ... Apparent magnitude: up to -12. ... Adjectives: Terrestrial, Terran, Telluric, Tellurian, Earthly Atmosphere Surface pressure: 101. ... It has been suggested that this article or section be merged into counter-Earth. ...


The planets in early Greek astronomy

The name "planet" comes from the Greek term πλανήτης, planētēs, meaning "wanderer", as ancient astronomers noted how certain lights moved across the sky in relation to the other stars. Five planets can be seen with the naked eye: Mercury, Venus, Mars, Jupiter, and Saturn. Sometimes the luminaries, the Sun and Moon, are added to the list of naked eye planets to make a total of seven. Since the planets disappear from time to time when they approach the Sun, careful attention is required to identify all five. Observations of Venus are not straightforward. Early Greeks thought that the evening and morning appearances of Venus represented two different objects, calling it Hesperus ("evening star") when it appeared in the western evening sky and Phosphorus ("light-bringer") when it appeared in the eastern morning sky. They eventually came to recognize that both objects were the same planet. Pythagoras is given credit for this realization. This article is about the planet. ... Adjectives: Venusian or (rarely) Cytherean Atmosphere Surface pressure: 9. ... Adjectives: Martian Atmosphere Surface pressure: 0. ... Adjectives: Jovian Atmosphere Surface pressure: 20–200 kPa[4] (cloud layer) Composition: ~86% H2 ~13% Helium 0. ... Adjectives: Saturnian Atmosphere Surface pressure: 140 kPa Composition: >93% hydrogen >5% helium 0. ... The luminaries were what traditional astrologers called the two astrological planets which were the brightest and most important objects in the heavens, that is, the Sun and the Moon The Sun and Moon were well-established rulers of the other planets, in accordance with the ancient doctrine of astrology of... It has been suggested that Classical Planets be merged into this article or section. ... The planet Venus has been explored several times. ... In Greek mythology, Hesperos (Greek (The Evening Star), sometimes Latinized as Hesperus) and Heosphoros (Morning Star) Latinized as Eosphorus are sons of the dawn goddess Eos (Roman Aurora), by starry Astraios. ...


The planets eventually received names drawn from Greek mythology. The equivalent names in Roman mythology are the basis for the modern English names of the planets.Number 7, Number 8 has excepted Bombay mission of border expand & recon battle. TERMINATE COMMUNICATIONS ..... The bust of Zeus found at Otricoli (Sala Rotonda, Museo Pio-Clementino, Vatican) Greek mythology is the body of stories belonging to the ancient Greeks concerning their gods and heroes, the nature of the world and their own cult and ritual practices. ... A head of Minerva found in the ruins of the Roman baths in Bath Roman mythology, the mythological beliefs of the people of Ancient Rome, can be considered as having two parts. ... In ancient times, only the Sun and Moon, a few hundred stars and the most easily visible planets had names. ...


Calendars

Many ancient calendars are based on the cycles of the Sun or Moon. The Hellenic calendar incorporated these cycles. A lunisolar calendar based on both cycles is difficult. Some Greek astronomers worked out calendars based on the eclipse cycle. A calendar is a system for assigning calendar dates to days. ... The Attic calendar is the name of the calendar used in Ancient Athens. ... A lunisolar calendar is a calendar whose date indicates both the moon phase and the time of the solar year. ... Time-lapse series of photos of the lunar eclipse of October 2004 as seen from Northern California. ...


Eudoxan astronomy

In classical Greece, astronomy was a branch of mathematics; astronomers sought to create geometrical models that could imitate the appearances of celestial motions. This tradition began with the Pythagoreans, who placed astronomy among the four mathematical arts (along with arithmetic, geometry, and music). The study of number comprising the four arts was later called the quadrivium. Euclid, Greek mathematician, 3rd century BC, as imagined by by Raphael in this detail from The School of Athens. ... 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. ... For other uses, see Music (disambiguation). ... A number is an abstract idea used in counting and measuring. ... The quadrivium comprised the four subjects taught in medieval universities after the trivium. ...


Although he was not a creative mathematician, Plato (427-347 BCE) included the quadrivium as the basis for philosophical education in the Republic. He encouraged a younger mathematician, Eudoxus of Cnidus (c. 410 BCE-c. 347 BCE), to develop a system of Greek astronomy. According to a modern historian of science, David Lindberg: For other uses, see Plato (disambiguation). ... Eudoxus of Cnidus (Greek Εύδοξος) (410 or 408 BC – 355 or 347 BC) was a Greek astronomer, mathematician, physician, scholar and friend of Plato. ...

In their work we find (1) a shift from stellar to planetary concerns, (2) the creation of a geometrical model, the "two-sphere model," for the representation of stellar and planetary phenomena, and (3) the establishment of criteria governing theories designed to account for planetary observations. (Lindberg 1992, p. 90)

The two-sphere model is a geocentric model. It divides the cosmos into two regions: Early printed rendition of the Ptolemaic system. ... The Ancient and Medieval cosmos as depicted in Peter Apians Cosmographia (Antwerp, 1539). ...

  • A spherical Earth, central and motionless (the sublunary sphere).
  • A spherical heavenly realm centered on the Earth, which may contain multiple rotating spheres made of aether
Renaissance woodcut illustrating the two-sphere model.
Renaissance woodcut illustrating the two-sphere model.

Plato's main books on cosmology are the Timaeus and the Republic. In them he described the two-sphere model and said there were eight circles or spheres carrying the seven planets and the fixed stars. He put the celestial objects in the following order, beginning with the one closest to Earth: The Sublunary Sphere is a concept derived from Greek astronomy. ... Chinese Wood (木) | Fire (火) | Earth (土) | Metal (金) | Water (æ°´) Hinduism and Buddhism The Pancha Mahabhuta (The Five Great Elements) Vayu/Pavan (Air/Wind) Agni/Tejas (Fire) Akasha (Aether) Prithvi/Bhumi (Earth) Ap/Jala (Water) Aether (also spelled ether) is a concept used in ancient and medieval science as a substance. ... Image File history File links Ptolemaicsystem-small. ... Image File history File links Ptolemaicsystem-small. ... Timaeus is a theoretical treatise of Plato in the form of a Socratic dialogue, written circa 360 BC. The work puts forward speculation on the nature of the physical world. ... Forms of government Part of the Politics series Politics Portal This box:      A republic is a form of government maintained by a state or country whose sovereignty is based on popular consent and whose governance is based on popular representation and control. ...

  1. Moon
  2. Sun
  3. Venus
  4. Mercury
  5. Mars
  6. Jupiter
  7. Saturn
  8. Fixed stars

According to the "Myth of Er" in the Republic, the cosmos is the Spindle of Necessity, attended by Sirens and spun by the three daughters of the Goddess Necessity known collectively as the Moirae or Fates. The Myth of Er is an analogy used in Platos Republic. ... To meet Wikipedias quality standards, this article or section may require cleanup. ... In Greek mythology, the Sirens or Seirenes (Greek Σειρῆνας) were sea nymphs who lived on an island called Sirenum scopuli which was surrounded by cliffs and rocks. ... Fates redirects here. ...


According to a story reported by Simplicius of Cilicia (6th century CE), Plato posed a question for the Greek mathematicians of his day: "By the assumption of what uniform and orderly motions can the apparent motions of the planets be accounted for?" (quoted in Lloyd 1970, p. 84). Plato proposed that the seemingly chaotic wandering motions of the planets could be explained by combinations of uniform circular motions centered on a spherical Earth, apparently a novel idea in the 4th century. Simplicius, a native of Cilicia, a disciple of Ammonius and of Damascius, was one of the last of the Neoplatonists. ...


Eudoxus rose to the challenge by assigning to each planet a set of concentric spheres. By tilting the axes of the spheres, and by assigning each a different period of revolution, he was able to approximate the celestial "appearances." Thus, he was the first to attempt a mathematical description of the motions of the planets. A general idea of the content of On Speeds, his book on the planets, can be gleaned from Aristotle's Metaphysics XII, 8, and a commentary by Simplicius on De caelo, another work by Aristotle. Since all his own works are lost, our knowledge of Eudoxus is obtained from secondary sources. Aratus's poem on astronomy is based on a work of Eudoxus, and possibly also Theodosius of Bithynia's Sphaerics. They give us an indication of his work in spherical astronomy as well as planetary motions. Concentric objects share the same center, axis or origin with one inside the other. ... Aristotle (Greek: Aristotélēs) (384 BC – 322 BC) was a Greek philosopher, a student of Plato and teacher of Alexander the Great. ... Metaphysics is one of the principal works of Aristotle and the first major work of the branch of philosophy with the same name. ... Aratus (Greek Aratos) (ca. ... A giant Hubble mosaic of the Crab Nebula, a supernova remnant Astronomy is the science of celestial objects (such as stars, planets, comets, and galaxies) and phenomena that originate outside the Earths atmosphere (such as auroras and cosmic background radiation). ... Theodosius of Bithynia (ca. ... Spherical astronomy is the branch of astronomy that is used to determine the location of objects on the celestial sphere, as seen at a particular date, time, and location on the Earth. ...


Callippus, a Greek astronomer of the 4th century, added seven spheres to Eudoxus' original 27 (in addition to the planetary spheres, Eudoxus included a sphere for the fixed stars). Aristotle described both systems, but insisted on adding "unrolling" spheres between each set of spheres to cancel the motions of the outer set. Aristotle was concerned about the physical nature of the system; without unrollers, the outer motions would be transferred to the inner planets. Callippus (or Calippus) (circa 370 B.C.–circa 300 B.C.) was a Greek astronomer. ...


Babylonian influence on Greek astronomy

To meet Wikipedias quality standards, this article or section may require cleanup. ...

Hellenistic astronomy

Planetary models and observational astronomy

The Eudoxan system had several critical flaws. One was its inability to predict motions exactly. Callippus' work may have been an attempt to correct this flaw. A related problem is the inability of his models to explain why planets appear to change speed. A third flaw is its inability to explain changes in the brightness of planets as seen from Earth. Because the spheres are concentric, planets will always remain at the same distance from Earth. This problem was pointed out in Antiquity by Autolycus of Pitane (c. 310 BCE). Autolycus of Pitane (c. ...


Apollonius of Perga (c. 262 BC–c. 190 BCE) responded by introducing two new mechanisms that allowed a planet to vary its distance and speed: the eccentric deferent and the deferent and epicycle. The deferent is a circle carrying the planet around the Earth. (The word deferent comes from the Latin ferro, ferre, meaning "to carry.") An eccentric deferent is slightly off-center from Earth. In a deferent and epicycle model, the deferent carries a small circle, the epicycle, which carries the planet. The deferent-and-epicycle model can mimic the eccentric model, as shown by Apollonius' theorem. It can also explain retrogradation, which happens when planets appear to reverse their motion through the zodiac for a short time. Modern historians of astronomy have determined that Eudoxus' models could only have approximated retrogradation crudely for some planets, and not at all for others. Apollonius of Perga [Pergaeus] (ca. ... Example of using eccentric on steam engine In mechanical engineering, an eccentric is a wheel that rotates on an axle that is displaced from the focus of the circle described by the wheel; in other words, a mechanical motion that can operate either as a cam or a crank, depending... In the Ptolemaic system of astronomy, the epicycle (literally: on the cycle in Greek) was a geometric model to explain the variations in speed and direction of the apparent motion of the Moon, Sun, and planets. ... Prograde motion is the motion of a planetary body in a direction similar to that of other bodies within its system, and is sometimes called direct motion, especially in astrology. ... It has been suggested that this article be split into multiple articles. ...


In the 2nd century BCE, Hipparchus, aware of the extraordinary accuracy with which Babylonian astronomers could predict the planets' motions, insisted that Greek astronomers achieve similar levels of accuracy. Somehow he had access to Babylonian observations or predictions, and used them to create better geometrical models. For the Sun, he used a simple eccentric model, based on observations of the equinoxes, which explained both changes in the speed of the Sun and differences in the lengths of the seasons. For the Moon, he used a deferent and epicycle model. He could not create accurate models for the remaining planets, and criticized other Greek astronomers for creating inaccurate models. Hipparchus. ... Babylonia was an ancient state in Iraq), combining the territories of Sumer and Akkad. ... In astronomy, an equinox is defined as the moment when the sun reaches one of two intersections between the ecliptic and the celestial equator. ... This article is about divisions of a year. ... In the Ptolemaic system of astronomy, the epicycle (literally: on the cycle in Greek) was a geometric model to explain the variations in speed and direction of the apparent motion of the Moon, Sun, and planets. ...


Hipparchus also compiled a star catalogue. According to Pliny the Elder, he observed a nova (new star). So that later generations could tell whether other stars came to be, perished, moved, or changed in brightness, he recorded the position and brightness of the stars. Ptolemy mentioned the catalogue in connetion with Hipparchus' discovery of precession. (Precession of the equinoxes is a slow motion of the place of the equinoxes through the zodiac, caused by the shifting of the Earth's axis). Hipparchus thought it was caused by the motion of the sphere of fixed stars. In astronomy, many stars are referred to simply by catalogue numbers. ... Pliny the Elder: an imaginative 19th Century portrait. ... Artists conception of a white dwarf star accreting hydrogen from a larger companion A nova (pl. ... A medieval artists rendition of Claudius Ptolemaeus Claudius Ptolemaeus (Greek: ; ca. ... Precession of the equinoxes is caused by a polar motion, a change in the orientation of the Earths axis. ... Precession of a gyroscope Precession refers to a change in the direction of the axis of a rotating object. ...


Heliocentrism and cosmic scales

In the 3rd century BCE, Aristarchus of Samos proposed an alternate cosmology (arrangement of the universe): a heliocentric model of the solar system, placing the Sun, not the Earth, at the center of the known universe (hence he is sometimes known as the "Greek Copernicus"). His astronomical ideas were not well-received, however, and only a few brief references to them are preserved. We know the name of one follower of Aristarchus: Seleucus of Seleucia. Statue of Aristarchus at Aristoteles University in Thessaloniki, Greece Aristarchus (310 BC - c. ... 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. ... 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. ... Major features of the Solar System (not to scale; from left to right): Pluto, Neptune, Uranus, Saturn, Jupiter, the asteroid belt, the Sun, Mercury, Venus, Earth and its Moon, and Mars. ... Nicolaus Copernicus (in Latin; Polish Mikołaj Kopernik, German Nikolaus Kopernikus - February 19, 1473 – May 24, 1543) was a Polish astronomer, mathematician and economist who developed a heliocentric (Sun-centered) theory of the solar system in a form detailed enough to make it scientifically useful. ... Seleucus (or Seleukos) of Seleucia (born circa 190 BC - ?) was a Greek philosopher. ...


Aristarchus also wrote a book On the Sizes and Distances of the Sun and Moon, which is his only work to have survived. In this work, he calculated the sizes of the Sun and Moon, as well as their distances from the Earth in Earth radii. Shortly afterwards, Eratosthenes calculated the size of the Earth, providing a value for the Earth radii which could be plugged into Aristarchus' calculations. Hipparchus wrote another book On the Sizes and Distances of the Sun and Moon, which has not survived. Both Aristarchus and Hipparchus drastically underestimated the distance of the Sun from the Earth. On the Sizes and Distances [of the Sun and Moon] is the only extant work written by Aristarchus of Samos, an ancient Greek astronomer who lived circa 310 BC - 230 BC. In this work, he calculates the sizes of the Sun and Moon, as well as their distances from the... Since the Earth, like all planets, is not a perfect sphere, the radius of Earth can refer to various values. ... Eratosthenes (Greek ; 276 BC - 194 BC) was a Greek mathematician, geographer and astronomer. ... On Sizes and Distances [of the Sun and Moon] (Peri megethoon kai apostèmátoon) is a text by the ancient Greek astronomer Hipparchus. ...


Astronomy in the Greco-Roman and Late Antique eras

Hipparchus is considered to have been among the most important Greek astronomers, because he introduced the concept of exact prediction into astronomy. He was also the last innovative astronomer before Claudius Ptolemy, a mathematician who worked at Alexandria in Roman Egypt in the 2nd century CE. Ptolemy's works on astronomy and astrology include the Almagest, the Planetary Hypotheses, and the Tetrabiblos, as well as the Handy Tables, the Canobic Inscription, and other minor works. A medieval artists rendition of Claudius Ptolemaeus Claudius Ptolemaeus (Greek: ; ca. ... Alexandria (Greek: , Coptic: , Arabic: , Egyptian Arabic: Iskindireyya), (population of 3. ... The Roman Empire ca. ... Hand-coloured version of the anonymous Flammarion woodcut. ... Almagest is the Latin form of the Arabic name (al-kitabu-l-mijisti, i. ... Claudius Ptolemaeus, given contemporary German styling, in a 16th century engraved book frontispiece Claudius Ptolemaeus (Greek: Κλαύδιος Πτολεμαῖος; c. ...


The Almagest 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, as Hipparchus could not, with the introduction of a new mathematical tool, the equant. The Almagest gave a comprehensive treatment of astronomy, incorporating theorems, models, and observations from many previous mathematicians. This fact may explain its survival, in contrast to more specialized works that were neglected and lost. Ptolemy placed the planets in the order that would remain standard until it was displaced by the heliocentric system and the Tychonic system: Equant is a mathematical concept developed by Claudius Ptolemy in the 2nd century AD to account for the observed motion of heavenly bodies. ... In astronomy, heliocentrism is the theory that the Sun is at the center of the Universe and/or the Solar System. ... Tychonic system The Tychonic system (or Tychonian system) was an effort by Tycho Brahe to create a model of the solar system which would combine what he saw as the mathematical benefits of the Copernican system with the philosophical and physical benefits of the Ptolemaic system. ...

  1. Moon
  2. Mercury
  3. Venus
  4. Sun
  5. Mars
  6. Jupiter
  7. Saturn
  8. Fixed stars

The extent of Ptolemy's reliance on the work of other mathematicians, in particular his use of Hipparchus' star catalogue, has been debated since the 19th century. A controversial claim was made by Robert R. Newton in the 1970s. in The Crime of Claudius Ptolemy, he argued that Ptolemy faked his observations and falsely claimed the catalogue of Hipparchus as his own work. Newton's theories have not been adopted by most historians of astronomy.


A few mathematicians of Late Antiquity wrote commentaries on the Almagest, including Pappus of Alexandria as well as Theon of Alexandria and his daughter Hypatia. Ptolemaic astronomy became standard in medieval western European and Islamic astronomy until it was displaced by heliocentric and Tychonic systems around 1600. However, recently discovered manuscripts reveal that Greek astrologers of Antiquity continued using pre-Ptolemaic methods for their calculations (Aaboe, 2001). Pappus of Alexandria is one of the most important mathematicians of ancient Greek time, known for his work Synagoge or Collection (c. ... Theon (c. ... Hypatia could refer to: Hypatia of Alexandria (?370–415), a neo-Platonic philosopher, mathematician, and teacher. ... This is a sub-article of Islamic science and astronomy. ... In astronomy, heliocentrism is the theory that the Sun is at the center of the Universe and/or the Solar System. ... Tychonic system The Tychonic system (or Tychonian system) was an effort by Tycho Brahe to create a model of the solar system which would combine what he saw as the mathematical benefits of the Copernican system with the philosophical and physical benefits of the Ptolemaic system. ... An astrological chart (or horoscope) _ Y2K Chart — This particular chart is calculated for January 1, 2000 at 12:01:00 A.M. Eastern Standard Time in New York City, New York, USA. (Longitude: 074W0023 - Latitude: 40N4251) Astrology (from Greek: αστρολ&#959...


Interactions with Indian astronomy

Further information: Indian astronomy
Greek equatorial sun dial, Ai-Khanoum, Afghanistan 3rd-2nd century BCE.
Greek equatorial sun dial, Ai-Khanoum, Afghanistan 3rd-2nd century BCE.

Hellenistic astronomy is known to have been practiced near India in the Greco-Bactrian city of Ai-Khanoum from the 3rd century BCE. Various sun-dials, including an equatorial sundial adjusted to the latitude of Ujjain have been found in archaeological excavations there.[1] Numerous interactions with the Mauryan Empire, and the later expansion of the Indo-Greeks into India suggest that some transmission may have happened during that period.[2] The astronomy and the astrology of Ancient India (Jyotisha) is based upon sidereal calculations. ... Image File history File linksMetadata No higher resolution available. ... Image File history File linksMetadata No higher resolution available. ... Sun Dial (occasionally spelled Sundial) is a British psychedelic rock band formed in 1990 by Gary Ramon. ... Hellenistic foot fragment of a giant statue, from Ai-Khanoum, 2nd century BCE. Ai-Khanoum or Ay Khanum (lit. ... The term Hellenistic (derived from HéllÄ“n, 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. ... The Greco-Bactrian Kingdom (or Graeco-Bactrian Kingdom) covered the areas of Bactria and Sogdiana, comprising todays northern Afghanistan and parts of Central Asia, the easternmost area of the Hellenistic world, from 250 to 125 BCE. The expansion of the Greco-Bactrians into northern India from 180 BCE established... Hellenistic foot fragment of a giant statue, from Ai-Khanoum, 2nd century BCE. Ai-Khanoum or Ay Khanum (lit. ... (4th century BC - 3rd century BC - 2nd century BC - other centuries) (2nd millennium BC - 1st millennium BC - 1st millennium AD) Events The first two Punic Wars between Carthage and Rome over dominance in western Mediterranean Rome conquers Spain Great Wall of China begun Indian traders regularly visited Arabia Scythians occupy... Ujjain   (Hindi:उज्जैन) (also known as Ujain, Ujjayini, Avanti, Avantikapuri) is an ancient city of central India, in the Malwa region of the Indian state of Madhya Pradesh, on the eastern bank of the Kshipra River. ... The Mauryan empire (321 to 185 BCE), at its largest extent around 230 BCE. The Lion Capital of Asoka, erected around 250 BCE. It is the emblem of India. ... The Indo-Greek Kingdom (or sometimes Graeco-Indian Kingdom[1]) covered various parts of the northwest and northern Indian subcontinent from 180 BCE to around 10 CE, and was ruled by a succession of more than thirty Hellenistic kings,[2] often in conflict with each other. ...


Several Greco-Roman astrological treatises are also known to have been imported into India during the first few centuries of our era. The Yavanajataka ("Sayings of the Greeks") was translated from Greek to Sanskrit by Yavanesvara during the 2nd century CE, under the patronage of the Western Satrap Saka king Rudradaman I. The Yavanajataka (Sanskrit for Saying (Jataka) of the Greeks (Yavanas)) is the earliest writing of Indian astrology. ... Yavanesvara (Sanskrit for Lord (Svara) of the Greeks (Yavanas)) was a man who lived in the Gujarat region of India under the rule of the Western Kshatrapa Saka king Rudrakarman I. In 149-150 CE, Yavanesvara translated from Greek to Sanskrit the Yavanajataka (Saying of the Greeks), one of the... The Western Satraps, or Western Kshatrapas (35-405) were Saka rulers of the western and central part of India (Saurashtra and Malwa: modern Gujarat, Maharashtra, Rajasthan and Madhya Pradesh states). ... A cataphract-style parade armour from gold scales of Sakas King found in Issyk in Kazakhstan in 1970[1] The Sakas were Iranian people stock who lived in what is now Kazakhstan, Uzbekistan, Tajikistan, Afghanistan, Pakistan and parts of Iran, Ukraine, and Altay Mountains and Siberia in Russia, in the... Rudradaman I was the Saka (Scythian) ruler of Malwa circa 50 BC. He was the grandson of the celebrated Scythian king Chastana. ...


Later in the 6th century, the Romaka Siddhanta ("Doctrine of the Romans"), and the Paulisa Siddhanta ("Doctrine of Paul") were considered as two of the five main astrological treatises, which were compiled by Varahamihira in his Pañca-siddhāntikā ("Five Treatises").[3] Varahamihira wrote in the Brihat-Samhita: "The Greeks, though impure, must be honored since they were trained in sciences and therein, excelled others....."[4] The Garga Samhita also says: "The Yavanas are barbarians, yet the science of astronomy originated with them and for this they must be reverenced like gods." The Romaka Siddhanta (literally Doctrine of the Romans) is an Indian astronomical treatise, based on the works of the ancient Romans. ... The Paulisa Siddhanta (litteraly, Doctrine of Paul) is an Indian astronomical treatise, based on the works of the Western scholar Paul of Alexandria (c. ... Paulus Alexandrinus was an astrological author from the late Roman Empire. ... Varahamihira (505 – 587) was an Indian astronomer, mathematician, and astrologer born in Ujjain. ... This volume of Varahamihira is an encyclopedia of wide ranging subjects of human interest, including astrology, planetary movements, eclipses, rainfall, clouds, architecture, growth of crops, manufacture of perfume, matrimony, domestic relations, gems, pearls, and rituals. ... Garga Samhita (The narrations of Garga) is a book written by the sage Garga and deals with the life of Krishna. ... Yona (also sometimes Yonaka) is a Pali word used in ancient India to designate ancient Greek people. ... Look up Barbarian in Wiktionary, the free dictionary. ...


However, this view has been disputed by some scholars who argue for an indigineous development of classical Indian astronomy and dismiss the possible Greek influences. They point to numerous similarities between Indian astronomy during the classical period and during the earlier pre-Hellenistic Vedic period. Some have also suggested the possibility of Pythagoras visiting India and learning the Vedic sciences and philosophy there, which in turn may have had an influence on early Greek sciences and philosophy.[5] Others have suggested mutual influence between Hellenistic and Indian astronomers, as it is known that Brahmins and Yogis were active in the Mediterranean.[5] According to this view, Vedic astronomy may have had an influence on some of the ideas of Hipparchus and Ptolemy.[5] The Vedic period (or Vedic Age) is the period in the history of India when the sacred Vedic Sanskrit texts such as the Vedas were composed. ... Pythagoras of Samos (Greek: ; circa 580 BC – circa 500 BC) was an Ionian (Greek) philosopher[1] and founder of the religious movement called Pythagoreanism. ... Vedic science may refer to a number of claims, ancient and modern, Hindu, occultist or New Age, of allegedly scientific systems of thought found in or based on the Vedas. ... The term Indian philosophy may refer to any of several traditions of philosophical thought, including: Hindu philosophy Buddhist philosophy Jain philosophy Sikh philosophy Carvaka atheist philosophy Lokayata materialist philosophy Tantric religious philosophy Bhakti religious philosophy Sufi religious philosophy Ahmadi religious philosophy Political and military philosophy such as that of Chanakya... Greek philosophy focused on the role of reason and inquiry. ... A Brahmin (anglicised from the Sanskrit adjective belonging to Brahma, also known as Brahman belonging to ; Vipra, Dvija twice-born, Dvijottama best of the twice born or earth-god) is considered to be the highest class (varna) in the Indian caste system of Hindu society [1] [2], although this status... It has been suggested that yogin be merged into this article or section. ... The Mediterranean Basin refers to the lands around and surrounded by the Mediterranean Sea. ... Hipparchus. ... A medieval artists rendition of Claudius Ptolemaeus Claudius Ptolemaeus (Greek: ; ca. ...


Sources for Greek astronomy

Many Greek astronomical texts are known only by name, and perhaps by a description or quotations. Some elementary works have survived because they were largely non-mathematical and suitable for use in schools. Books in this class include the Phaenomena of Euclid and two works by Autolycus of Pitane. Three important textbooks, written shortly before Ptolemy's time, were written by Cleomedes, Geminus, and Theon of Smyrna. Books by Roman authors like Pliny the Elder and Vitruvius contain some information on Greek astronomy. The most important primary source is the Almagest, since Ptolemy refers to the work of many of his predecessors (Evans 1998, p. 24). Euclid (Greek: ), also known as Euclid of Alexandria, was a Greek mathematician who flourished in Alexandria, Egypt, almost certainly during the reign of Ptolemy I (323–283 BC). ... Autolycus of Pitane (c. ... Cleomedes was a Greek astronomer who is known chiefly for his book On the Circular Motions of the Celestial Bodies. ... Geminus of Rhodes was a Greek astronomer and mathematician. ... Theon of Smyrna (ca. ... Marcus Vitruvius Pollio (born ca. ...


Famous astronomers of antiquity

In addition to the authors named in the article, the following list of people who worked on mathematical astronomy or cosmology may be of interest.

Pythagoras
Pythagoras

Image File history File links No higher resolution available. ... Image File history File links No higher resolution available. ... Anaxagoras Anaxagoras (Greek: Αναξαγόρας, c. ... Engraved portrait of Apollonius of Tyana. ... Archimedes (Greek: c. ... Archytas Archytas (428 BC - 347 BC) was a Greek philosopher, mathematician, astronomer, statesman, strategist and commander-in-chief. ... A minor god in Greek mythology, Aristaeus or Aristaios was the son of Apollo and the huntress Cyrene, who despised spinning and other womanly arts but spent her days hunting. ... For the crater, see Aristillus (crater). ... Conon of Samos (circa 280 BC - circa: 220 BC) was a Greek mathematician and astronomer. ... ‎ Democritus (Greek: ) was a pre-Socratic Greek philosopher (born at Abdera in Thrace around 460 BC). ... For the volcano, see Empedocles (volcano). ... Heraclides Ponticus (387 - 312 BCE), also known as Heraklides, was a Greek philosopher who lived and died at Heraclea, now Eregli, Turkey. ... Hicetas (around 400 BC – around 335 BC) was a Greek philosopher of the Pythagorean School. ... Hippocrates of Chios was an ancient Greek mathematician (geometer) and astronomer, who lived c. ... Ambrosius Theodosius Macrobius, Roman grammarian and philosopher, flourished during the reigns of Honorius and Arcadius (395-423). ... Martianus Minneus Felix Capella was a writer of the late Latin period, whose career flourished some time during the 5th century, before the year 439. ... Menelaus of Alexandria (born ca. ... Menelaus theorem (also known as Menelaus theorem, Menelauss theorem, as well as theorem of Menelaus; attributed to Menelaus of Alexandria) is a theorem about triangles in plane geometry. ... 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. ... Parmenides of Elea (Greek: , early 5th century BC) was an ancient Greek philosopher born in Elea, a Hellenic city on the southern coast of Italy. ... Porphyry (Greek: , c. ... The bust of Posidonius as an older man depicts his character as a Stoic philosopher. ... Proclus Lycaeus (February 8, 412 – April 17, 485), surnamed The Successor or diadochos (Greek Πρόκλος ὁ Διάδοχος Próklos ho Diádokhos), was a Greek Neoplatonist philosopher, one of the last major Greek philosophers (see Damascius). ... Pythagoras of Samos (Greek: ; circa 580 BC – circa 500 BC) was an Ionian (Greek) philosopher[1] and founder of the religious movement called Pythagoreanism. ... This article or section is not written in the formal tone expected of an encyclopedia article. ... Theodosius of Bithynia (ca. ...

See also

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. ... Astronomy is probably the oldest of the natural sciences, dating back to antiquity, with its origins in the religious practices of pre-history: vestiges of these are still found in astrology, a discipline long interwoven with astronomy, and not completely different from it until about 1750‑1800 in the Western... To meet Wikipedias quality standards, this article or section may require cleanup. ...

Notes

  1. ^ "Afghanistan, les trésors retrouvés", p269
  2. ^ "Les influences de l'astronomie grecques sur l'astronomie indienne auraient pu commencer de se manifester plus tot qu'on ne le pensait, des l'epoque Hellenistique en fait, par l'intermediaire des colonies grecques des Greco-Bactriens et Indo-Grecs" (French) Afghanistan, les trésors retrouvés", p269. Translation: "The influence of Greek astronomy on Indian astronomy may have taken place earlier than thought, as soon as the Hellenistic period, through the agency of the Greek colonies of the Greco-Bactrians and the Indo-Greeks.
  3. ^ "the Pañca-siddhāntikā ("Five Treatises"), a compendium of Greek, Egyptian, Roman and Indian astronomy. Varāhamihira's knowledge of Western astronomy was thorough. In 5 sections, his monumental work progresses through native Indian astronomy and culminates in 2 treatises on Western astronomy, showing calculations based on Greek and Alexandrian reckoning and even giving complete Ptolemaic mathematical charts and tables. Encyclopedia Britanica Vol12, p269 Source
  4. ^ ":Mleccha hi yavanah tesu samyak shastram idam sthitam
    Rsivat te api pujyante kim punar daivavid dvijah
    -(Brhatsamhita 2.15)
  5. ^ a b c Richard L. Thompson (2003). Vedic Cosmography and Astronomy, p. 15-17, 181-198. Motilal Banarsidass Publ. ISBN 8120819543.

References

  • Aaboe, Asger. Episodes from the Early History of Astronomy. Springer, 2001.
  • Dreyer, J. L. E. A History of Astronomy from Thales to Kepler. New York: Dover Publications, 1953.
  • Evans, James. The History and Practice of Ancient Astronomy. New York: Oxford University Press, 1998.
  • Heath, Thomas. Aristarchus of Samos. Oxford: Clarendon Press, 1913.
  • Lindberg, David C. The Beginnings of Western Science: The European Scientific Tradition in Philosophical, Religious, and Institutional Context, 600 B.C. to A.D. 1450. Chicago: University of Chicago Press, 1992.
  • Lloyd, G. E. R. Early Greek Science: Thales to Aristotle. New York: W.W. Norton & Co., 1970.
  • Neugebauer, Otto. A History of Ancient Mathematical Astronomy. 3 vols. Berlin: Springer, 1975. (Commonly abbreviated as HAMA)
  • Newton, Robert R. The Crime of Claudius Ptolemy. Baltimore: Johns Hopkins University Press, 1977.
  • Pedersen, Olaf. Early Physics and Astronomy: A Historical Introduction. 2nd edition. Cambridge: Cambridge University Press, 1993.

John Louis Emil Dreyer (February 13, 1852 – September 14, 1926) was a Danish-Irish astronomer. ... Thomas Little Heath (October 5, 1861 - March 16, 1940) was a mathematician, classical scholar, historian of ancient Greek mathematics, and translator. ... 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. ...

External links

  • Almagest Planetary Model Animations
  • MacTutor History of Mathematics Archive

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