Editing Hipparchus (section)

==Life and work==
Hipparchus was born in Nicaea ({{langx|grc|Νίκαια}}), in [[Bithynia]]. The exact dates of his life are not known, but [[Ptolemy]] attributes astronomical observations to him in the period from 147 to 127&nbsp;BC, and some of these are stated as made in [[Rhodes]]; earlier observations since 162&nbsp;BC might also have been made by him. His birth date ({{c.|lk=no|190}}&nbsp;BC) was calculated by [[Jean Baptiste Joseph Delambre|Delambre]] based on clues in his work. Hipparchus must have lived some time after 127&nbsp;BC because he analyzed and published his observations from that year. Hipparchus obtained information from [[Alexandria]] as well as [[Babylon]], but it is not known when or if he visited these places. He is believed to have died on the island of Rhodes, where he seems to have spent most of his later life.

In the second and third centuries, [[coin]]s were made in his honour in Bithynia that bear his name and show him with a [[globe]].<ref>{{cite web |title=Ancient coinage of Bithynia |url=http://snible.org/coins/hn/bithynia.html |website=snible.org |access-date=26 April 2021}}</ref>

Relatively little of Hipparchus's direct work survives into modern times. Although he wrote at least fourteen books, only his commentary on the popular astronomical poem by [[Aratus]] was preserved by later copyists. Most of what is known about Hipparchus comes from [[Strabo]]'s ''[[Geographica|Geography]]'' and [[Pliny the Elder|Pliny]]'s ''[[Natural History (Pliny)|Natural History]]'' in the first century; Ptolemy's second-century ''[[Almagest]]''; and additional references to him in the fourth century by [[Pappus of Alexandria|Pappus]] and [[Theon of Alexandria]] in their commentaries on the ''Almagest''.{{sfn|Toomer|1978}}{{sfn |Jones |2001}}

Hipparchus's only preserved work is ''Commentary on the Phaenomena of Eudoxus and Aratus'' ({{langx|grc|Τῶν Ἀράτου καὶ Εὐδόξου φαινομένων ἐξήγησις}}). This is a highly critical commentary in the form of two books on a popular [[poem]] by [[Aratus]] based on the work by [[Eudoxus of Cnidus|Eudoxus]].<ref>Modern editions: {{harvnb| Manitius|1894}} (Ancient Greek and Latin), {{harvnb|Cusinato|Vanin|2022}} (Italian)</ref> Hipparchus also made a list of his major works that apparently mentioned about fourteen books, but which is only known from references by later authors. His famous star catalog was incorporated into the one by Ptolemy and may be almost perfectly reconstructed by subtraction of two and two-thirds degrees from the longitudes of Ptolemy's stars {{citation needed|date=September 2024}}{{dubious|date=September 2024}}. The first trigonometric table was apparently compiled by Hipparchus, who is consequently now known as "the father of trigonometry".