According to Aristotle, it was Thessalos, the hot-headed son of Peisistratus ´ Argive concubine and thus half-brother to Hipparchus, who was the one to court Harmodius and drive off his sister.

It was not separated from Centaurus until Hipparchus of Bithynia named it Therion ( meaning beast ) in the 200s BCE.

This can be dated back to Hipparchus, who around 190 BC used the catalogue of his predecessors Timocharis and Aristillus to discover the earth ’ s precession.

Hipparchus of Nicaea, or more correctly Hipparchos (; c. 190 BC – c. 120 BC ), was a Greek astronomer, geographer, and mathematician of the Hellenistic period.

Hipparchus ( 190 – 120 BC ), focusing on astronomy and mathematics, used sophisticated geometrical techniques to map the motion of the stars and planets, even predicting the times that solar eclipses would happen.

The star catalog of Hipparchus ( 2nd century BC ) included 1020 stars and was used to assemble Ptolemy's star catalogue.

The Hellenistic astronomers Hipparchus ( c. 150 BC ) and Ptolemy ( c. AD 150 ) subdivided the day sexagesimally and also used a mean hour, simple fractions of an hour (,, etc.

Hipparchus ( c. 190 – c. 120 BC ) completed his star catalogue in 129 BC, which he compared to Timocharis ' and discovered that the longitude of the stars had changed over time.

Hipparchus in the 2nd century BC enumerated about 850 stars.

The tyrant Peisistratos had died in 527 BC, passing power to his sons, Hipparchus and Hippias.

Hipparchus was murdered in 514 BC, and in response to this, Hippias became paranoid and started to rely increasingly on foreign mercenaries to keep a hold on power.

Ptolemy lived in the 2nd century AD, three centuries after the discovery of the precession of the equinoxes by Hipparchus around 130 BC, but he ignored the problem by dropping the concept of a fixed celestial sphere and adopting what is referred to as a tropical coordinate system instead.

** Hipparchus, Greek astronomer, geographer, and mathematician ( d. c. 120 BC )

Bacchylides's career as a poet probably benefitted from the high reputation of his uncle, Simonides, whose patrons, when Bacchylides was born, already included Hipparchus, tyrant of Athens 527 – 14 BC.

* 150 BC – Hipparchus uses parallax to determine that the distance to the Moon is roughly 380, 000 km

* 134 BC – Hipparchus discovers the precession of the equinoxes

* 134 BC — Hipparchus creates the magnitude scale of stellar apparent luminosities

134 BC — Hipparchus makes a detailed star map

* Hipparchus, Greek astronomer, geographer, and mathematician ( d. c. 120 BC )

* Hipparchus, Greek astronomer and mathematician, on Rhodes ( approximate date ) ( b. c. 190 BC )

In the 2nd century BC Hipparchus of Nicea made a number of contributions, including the first measurement of precession and the compilation of the first star catalog in which he proposed the modern system of apparent magnitudes.

Though there is still-controversial evidence that Aristarchus of Samos possessed distinct values for the sidereal and tropical years as early as c. 280 BC, the discovery of precession is usually attributed to Hipparchus ( 190 – 120 BC ) of Rhodes or Nicaea, a Greek astronomer.

We find Hipparchus ' mathematical signatures in the Antikythera Mechanism, an ancient astronomical computer of the 2nd century BC.

An early astrolabe was invented in the Hellenistic world in 150 BC and is often attributed to Hipparchus.

Ptolemy's catalogue was based almost entirely on an earlier one by Hipparchus ( Newton 1977 ; Rawlins 1982 ).

According to Ptolemy's Almagest, Hipparchus measured the longitude of Spica and other bright stars.

Hipparchus wrote about trigonometry, but because his works are no longer extant, mathematicians use Ptolemy's book as their source for Hipparchus ' works and ancient Greek trigonometry in general.

Its list of forty-eight constellations is ancestral to the modern system of constellations, but unlike the modern system they did not cover the whole sky ( only the sky Hipparchus could see ).

Hipparchus confirmed this value for the lunation length.

He also confirmed that precession affected all fixed stars, not just those near the ecliptic, and his cycle had same period of 36000 years as found by Hipparchus.

He used Hipparchus ' model to calculate the Sun's longitude, and made corrections for the Moon's motion and its parallax ( Evans 1998, pp. 251 – 255 ).

However, because the globe contains no actual stars, and because the circles on the globe are drawn inexactly and ambiguously by a sculptor copying the Hellenistic model rather than by a modern astronomer, the dating of the globe is still uncertain and its source or sources remain controversial ; Schaefer's conclusions have been strongly contested ( e. g., Dennis Duke, Journal for the History of Astronomy, February, 2006 ) most particularly on the ground that regardless of the globe's date the constellations on it show large disagreements with the only existing work by Hipparchus.

The founder of the mathematical school was the celebrated Euclid ; among its scholars were Archimedes ; Apollonius of Perga, author of a treatise on Conic Sections ; Eratosthenes, to whom we owe the first measurement of the earth ; and Hipparchus, the founder of the epicyclical theory of the heavens, afterwards called the Ptolemaic system, from its most famous expositor, Claudius Ptolemy.

Various assertions have been made that other cultures discovered precession independent of Hipparchus.

Linguistically, the association of horse ownership with social status extends back at least as far as ancient Greece, where many aristocratic names incorporated the Greek word for horse, like Hipparchus and Xanthippe ; the character Pheidippides in Aristophanes ' Clouds has his grandfather's name with hipp-inserted to sound more aristocratic.

Hipparchus compiled a catalogue with at least 850 stars and their positions.

Like the earlier catalogs of Hipparchus and Ptolemy, Ulugh Beg's catalogue is estimated to have been precise to within approximately 20 minutes of arc.

Hipparchus also gave an estimate of the distance of the Sun from the Earth, quoted by Pappus as equal to 490 Earth radii.

Hipparchus, brother of the tyrant Hippias, was killed by Harmodius and Aristogeiton, who were subsequently honored by the Athenians for their alleged restoration of Athenian freedom.

Greek historian Plutarch discusses an argument between Chrysippus ( 3rd century BCE ) and Hipparchus ( 2nd century BCE ) of a rather delicate enumerative problem, which was later shown to be related to Schröder numbers.

Hipparchus.

Hipparchus was born in Nicaea, Bithynia ( now Iznik, Turkey ), and probably died on the island of Rhodes.

Hipparchus is considered the greatest ancient astronomical observer and, by some, the greatest overall astronomer of antiquity.

It would be three centuries before Claudius Ptolemaeus ' synthesis of astronomy would supersede the work of Hipparchus ; it is heavily dependent on it in many areas.

An important role in this standardisation appears to have been played by the Athenian tyrant Hipparchus, who reformed the recitation of Homeric poetry at the Panathenaic festival.

Although he wrote at least fourteen books, almost nothing of Hipparchus ' direct work survived.

Although Greek astronomers had known, at least since Hipparchus, that the tropical year was a few minutes shorter than 365. 25 days, the calendar did not compensate for this difference.

These included notable thinkers such as Euclid, Archimedes, Eratosthenes, Herophilus, Erasistratus, Hipparchus, Aedesia, Pappus, Hypatia, Aristarchus of Samos, and Saint Catherine.

A later developer in this tradition was Hipparchus.

A central problem was that of projectile motion, which was discussed by Hipparchus and Philoponus.

Taking a different view from other modern scholars, Ulansey argues that the Mithraic mysteries began in the Greco-Roman world as a religious response to the discovery by the Greek astronomer Hipparchus of the astronomical phenomenon of the precession of the equinoxes – a discovery that amounted to discovering that the entire cosmos was moving in a hitherto unknown way.

He calculates the latitudes to be 64 ° 32 ′ and 65 ° 31 ′, supporting Hipparchus ' statement of the latitude of Thule.