Sosigenes of Alexandria
Σωσιγένης ὁ Ἀλεξανδρεύς
|Known for||Consulted by Julius Caesar for the design of the Julian calendar|
Sosigenes of Alexandria (Greek : Σωσιγένης ὁ Ἀλεξανδρεύς) was a Greek astronomer from Ptolemaic Egypt who, according to Roman historian Pliny the Elder, was consulted by Julius Caesar for the definition of the Julian calendar.
This year format pre-existed it being called Julian and was in use by astronomers. It is found in the Antikythera Mechanism.
Little is known about him apart from Pliny's Natural History . Sosigenes appears in Book 18, 210-212:
In Book 2, chapter 6, Sosigenes is credited with work on the orbit of Mercury:
The introduction of the Julian year was in 46 BC. This particular year lasted 445 days in Rome to correct the old Roman calendar that was totally erroneous. The Julian calendar is still in use by the astronomers and space missions.[ citation needed ]
Some sources state that the Julian calendar was designed by Aristarchus of Samos [ citation needed ], although it is not clear where this conclusion originates. Ptolemy III Euergetes, Aristarchus' contemporary, did indeed decree a reform of the Egyptian calendar in 238 BC, but it was never implemented.[ citation needed ] The reform, however, would have added an extra day (leap day) to the 365-day Egyptian calendar every four years, a feature shared by the Julian calendar.[ citation needed ]
Sosigenes wrote several books. We only have the titles of three of them: 1) essay on Aristotle «Υπόμνημα επί Αριστοτέλη» 2) The Sky «Περί Ουρανού» 3) Optics «Περί όψεως».
Sosigenes was portrayed by Hume Cronyn in the 1963 movie Cleopatra . This portrayal is heavily fictionalized: he serves as Cleopatra's tutor/adviser and later her envoy to Rome. He is ultimately murdered in the Forum by Octavian, commencing his war against Egypt. None of these events are present in historical record, and were invented for the film.
The Julian calendar, proposed by Julius Caesar in AUC 708, was a reform of the Roman calendar. It took effect on 1 January AUC 709 , by edict. It was designed with the aid of Greek mathematicians and astronomers such as Sosigenes of Alexandria.
Eratosthenes of Cyrene was a Greek polymath: a mathematician, geographer, poet, astronomer, and music theorist. He was a man of learning, becoming the chief librarian at the Library of Alexandria. His work is comparable to what is now known as the study of geography, and he introduced some of the terminology still used today.
Year 34 BC was either a common year starting on Friday, Saturday or Sunday or a leap year starting on Friday or Saturday of the Julian calendar and a common year starting on Friday of the Proleptic Julian calendar. At the time, it was known as the Year of the Consulship of Antonius and Libo. The denomination 34 BC for this year has been used since the early medieval period, when the Anno Domini calendar era became the prevalent method in Europe for naming years.
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Cleopatra VII Philopator was queen of the Ptolemaic Kingdom of Egypt, and its last active ruler. A member of the Ptolemaic dynasty, she was a descendant of its founder Ptolemy I Soter, a Macedonian Greek general and companion of Alexander the Great. After the death of Cleopatra, Egypt became a province of the Roman Empire, marking the end of the second to last Hellenistic state and the age that had lasted since the reign of Alexander. Her native language was Koine Greek, and she was the only Ptolemaic ruler to learn the Egyptian language.
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The history of science in early cultures covers protoscience in ancient history, prior to the development of science in the Middle Ages. In prehistoric times, advice and knowledge was passed from generation to generation in an oral tradition. The development of writing enabled knowledge to be stored and communicated across generations with much greater fidelity. Combined with the development of agriculture, which allowed for a surplus of food, it became possible for early civilizations to develop and spend more of their time devoted to tasks other than survival, such as the search for knowledge for knowledge's sake.
The history of science in classical antiquity encompasses both those inquiries into the workings of the universe aimed at such practical goals as establishing a reliable calendar or determining how to cure a variety of illnesses and those abstract investigations known as natural philosophy. The ancient peoples who are considered the first scientists may have thought of themselves as natural philosophers, as practitioners of a skilled profession, or as followers of a religious tradition. The encyclopedic works of Aristotle, Archimedes, Hippocrates, Galen, Ptolemy, Euclid, and others spread throughout the world. These works and the important commentaries on them were the wellspring of science.
Meton of Athens was a Greek mathematician, astronomer, geometer, and engineer who lived in Athens in the 5th century BC. He is best known for calculations involving the eponymous 19-year Metonic cycle which he introduced in 432 BC into the lunisolar Attic calendar. Euphronios says that Colonus was Meton's deme.
Pothinus or Potheinos, a eunuch, was regent for Pharaoh Ptolemy XIII Theos Philopator of the Ptolemaic Kingdom. He is most remembered for turning Ptolemy against his sister and co-ruler Cleopatra, thus starting a civil war, and for having Pompey decapitated and presenting the severed head to Julius Caesar.
Sosigenes the Peripatetic was a philosopher living at the end of the 2nd century AD. He was the tutor of Alexander of Aphrodisias and wrote a work On Revolving Spheres, from which some important extracts have been preserved in Simplicius's commentary on Aristotle's De Caelo.
Greek astronomy is astronomy written in the Greek language in classical antiquity. Greek astronomy is understood to include the ancient Greek, Hellenistic, Greco-Roman, and Late Antiquity eras. It is not limited geographically to Greece or to 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.
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The Ptolemaic Kingdom was an ancient Hellenistic state based in Egypt. It was founded in 305 BC by Ptolemy I Soter, a companion of Alexander the Great, and lasted until the death of Cleopatra VII in 30 BC. Ruling for nearly three centuries, the Ptolemies were the longest and final Egyptian dynasty of ancient origin.
The reign of Cleopatra VII of the Ptolemaic Kingdom of Egypt began with the death of her father, the ruling pharaoh Ptolemy XII Auletes, by March 51 BC. It ended with her death on 10 or 12 August 30 BC. Following the reign of Cleopatra, the country of Egypt was transformed into a province of the Roman Empire and the Hellenistic period came to an end. During her reign she ruled Egypt and other territories as an absolute monarch, in the tradition of the Ptolemaic dynasty's founder Ptolemy I Soter as well as Alexander the Great of Macedon, who captured Egypt from the Achaemenid Persian Empire.
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