They are mentioned by Ptolemy, who explains precession as the rotation of the celestial sphere around a motionless Earth.

Ptolemy explains Hipparchus ' discovery of the precession of the equinoxes and begins explaining the theory of epicycles.

Their official web page explains, " Ptolemy is a tortoise who lives at Terrascope Towers.

Ptolemy explains that such considerations are only dealt with summarily, as a background consideration for what follows.

Within his Almagest Ptolemy explains that he had access to eclipse records kept for 900 years since the beginning of the reign of king Nabonassar ( 747 BC ).

Ptolemy explains the order by which each theme becomes relevant, and follows this in his arrangement of topics presented in the remaining chapters of books III and IV.

was further advanced in India, and, in particular, the modern definitions of sine and cosine were developed there .< ref >: " As for trigonometry, it is disdained by geometers and abandoned to surveyors and astronomers ; it is these latter ( Aristarchus, Hipparchus, Ptolemy ) who establish the fundamental relations between the sides and angles of a right angled triangle ( plane or spherical ) and draw up the first tables ( they consist of tables giving the chord of the arc cut out by an angle < math >

Under the Greeks, and Ptolemy in particular, the planets, Houses, and signs of the zodiac were rationalized and their function set down in a way that has changed little to the present day.

), which suggests use of sidereal zodiac in Greece before Ptolemy and Hipparchus.

Ptolemy instructing Regiomontanus under an image of the zodiac encircling the celestial spheres.

In Ptolemy ’ s era the boundaries of the zodiac signs were close to those of the visible constellations whose names they bear, but Ptolemy demonstrates the theoretical distinction between the two frames of reference in describing the starting point of the zodiac as fixed, not to the stars, but to the mathematically calculated vernal equinox.

Ptolemy extends the logic given in ancient Babylonian texts where the four quarters of the known world are attributed to the four triplicity arrangements of the zodiac.

Though Ptolemy describes his analysis as a " brief exposition ", the chapter builds into an extensive association between planets, zodiac signs and the national characteristics of 73 nations.

A second possible solution is that these Angles of Ptolemy are not those of Schleswig at all.

On the map of Ptolemy, the " Kimbroi " are placed on the northernmost part of the peninsula of Jutland., i. e. in the modern landscape of Himmerland south of Limfjorden ( since Vendsyssel-Thy north of the fjord was at that time a group of islands ).

By AD 139, the geographer Ptolemy writes that the " Huni " ( Χοῦνοι or Χουνοἰ ) are between the Bastarnae and the Roxolani in the Pontic area under the rule of Suni.

The majority are Norse or Gaelic but the roots of several of the Hebrides may have a pre-Celtic origin and indeed the Haiboudai recorded by Ptolemy may itself be pre-Celtic.

In the geographers of the late Roman Republic and early Roman Empire, such as Ptolemy, Scythia stretches eastward from the mouth of the Vistula ; thus Pytheas must have described the Germanic coast of the Baltic sea ; if the statement is true, there are no other possibilities.

It seems likely that the topographical tables in books 2 – 7 are cumulative texts – texts which were altered and added to as new knowledge became available in the centuries after Ptolemy ( Bagrow 1945 ).

Because Ptolemy derived many of his key latitudes from crude longest day values, his latitudes are erroneous on average by roughly a degree ( 2 degrees for Byzantium, 4 degrees for Carthage ), though capable ancient astronomers knew their latitudes to more like a minute.

There are several characters or items named after Ptolemy, including:

They are assumed to have been the descendants of the Caledonii and other tribes named by Roman historians or found on the world map of Ptolemy.

Two other fragmentary copies of the same decree were discovered later, and several similar Egyptian bilingual or trilingual inscriptions are now known, including two slightly earlier Ptolemaic decrees ( the Decree of Canopus in 238 BC, and the Memphis decree of Ptolemy IV, ca.

* The fundamental works of Ptolemy on cartography are published.

It seems to have received a colony in the time of Augustus, whence we find mention in inscriptions of the Ordo et Populus splendidissimae Coloniae Augustae Himeraeorum Thermitanorum: and there can be very little doubt that the Thermae colonia of Pliny in reality refers to this town, though he evidently understood it to be Thermae Selinuntiae ( modern Sciacca ), as he places it on the south coast between Agrigentum ( modern Agrigento ) and Selinus There are little subsequent account of Thermae ; but, as its name is found in Ptolemy and the Itineraries, it appears to have continued in existence throughout the period of the Roman Empire, and probably never ceased to be inhabited, as the modern town of Termini Imerese retains the ancient site as well as name.

Shown are the typical Asturian cottages, which were already in use in the time of the AsturesClassical geographers give conflicting views of the ethnic description of the above mentioned peoples: Ptolemy says that the Astures extended along the central area of current Asturias, between the Navia and Sella rivers, fixing the latter river as the boundary with the Cantabrian territory.

* The children of Cleopatra are spared by Octavian and taken back in triumph ; Octavia Minor raised Alexander Helios, Cleopatra Selene and Ptolemy Philadelphus in her household in Rome.

Though the Romans send ambassadors to Ptolemy V, they are unable to lend him any serious assistance against Antiochus III.

* Following the defection of one of Ptolemy IV's leading commanders, Egypt's Syrian territories are seriously threatened by Antiochus III, thus initiating the Fourth Syrian War.

Other well-known examples are the Memphis Stele ( Memphis Stone ), bearing the Decree of Memphis, about 218 BC, passed by his son, Ptolemy IV, and the famous Rosetta Stone erected by Ptolemy Epiphanes, his grandson, in 196 BC.

* Judea and Syria are annexed by Ptolemy and he gives Judea a large measure of self-government.

The exact dates of his life are not known, but astronomical observations attributed to him by Ptolemy date from 147 BC to 127 BC.

Ptolemy II's ambitions in the Aegean Sea are threatened by Antigonus Gonatas ' fleet, so he carefully builds up a coalition against Macedonia in Greece.

Both are close to the values later used by Hipparchus and Ptolemy, and the precession indicated is almost precisely 1 degree per century, a value which is too low.

Ptolemy and Lysimachus are confirmed as satraps of Egypt and Thrace, respectively, and Antigonus and Cassander are confirmed as commanders of the army in Asia and Europe.

Seleucus II was soon dramatically defeated in the Third Syrian War against Ptolemy III of Egypt and then had to fight a civil war against his own brother Antiochus Hierax.

Ptolemy III did not issue coins with his own image.

He produced his own atlas in a number of parts, the first of which was published in 1578 and consisted of corrected versions of the maps of Ptolemy ( though introducing a number of new errors ).

* Berenice, daughter of Ptolemy II Philadelphus and Arsinoe, wife of the Seleucid ruler Antiochus II Theos, supplanting his first wife, Laodice, whose children she has persuaded him to bar from the succession to the throne in favour of her own

Ptolemy compared his own observations with those made by Hipparchus, Menelaus of Alexandria, Timocharis, and Agrippa.

To approximate his tropical year Hipparchus created his own lunisolar calendar by modifying those of Meton and Callippus in On Intercalary Months and Days ( now lost ), as described by Ptolemy in the Almagest III. 1 ( Toomer 1984, p. 139 ).

The Antiochenians offered the Seleucid throne to Ptolemy VI, who had already conquered most of southern Syria for his own interest.

He now prepared a large army and a formidable fleet, the command of which he gave to Demetrius, and hastened to attack Ptolemy in his own dominions.

The most powerful dynasts of the empire, now kings in their own right, Cassander, Seleucus, Ptolemy and Lysimachus, responded to Antigonus's successes by allying each other, often through marriage.

She was the mother of Ptolemy V. In summer, 204 BC she was murdered in a palace coup, shortly after her husband's own death.

At this time Ptolemy VIII murdered both his stepson Ptolemy and his own son Ptolemy Memphites.

Bosworth writes that " not only has it been virtually disproved that Ptolemy constructed his history from archival material, but it appears that he inserted his own propaganda to exaggerate his personal achievements under Alexander and to discredit those of his rivals ".

Although Ptolemy relied mainly on the work of Hipparchus, he introduced at least one idea, the equant, which appears to be his own, and which greatly improved the accuracy of the predicted positions of the planets.

Nevertheless, Egyptians asked the Romans to settle dynastic conflicts During his reign, Ptolemy XII attempted to secure his own fate and the fate of his dynasty by means of a pro-Roman policy.

Since the Senate was busy with its own affairs, Pompey ( as Ptolemy XII's ally ) approved the will.

The Brahmasphutasiddhanta is the earliest known text to treat zero as a number in its own right, rather than as simply a placeholder digit in representing another number as was done by the Babylonians or as a symbol for a lack of quantity as was done by Ptolemy and the Romans.

However, as Alexander the Great's empire disintegrated, Ptolemy soon established himself as ruler in his own right.

He was then killed in battle, and Ptolemy IX reigned until his own death.

Arsinoe herself fled to Egypt, where she married her own brother Ptolemy II and became Arsinoe II.

Ptolemy does not include the Carpi in his list of tribes resident in Dacia proper, even though this region, according to his own definition, comprised the whole Carpathian range.

During the Hellenistic era it was subject at various times to Alexander the Great, Lysimachus, Ptolemy II, and Philip V, and was at one time overrun by the Celts, but usually maintained its own kings.

At some time after Ptolemy the lowlands around and in what was once the Zuider Zee, now part of the Netherlands, became occupied by a people called the Salii (" salt-water people "), no doubt by a simple change of name, either their own or someone else's.

Ptolemy states in the letter that, " this division of the law ( that is, god's own law ) was established neither by the perfect god, as we have taught, nor surely by the devil-which it would be wrong to say-then the establisher of this division is distinct from them.