when was it published?
2nd-century.
Almagest
The Almagest is a 2nd-century Greek-language mathematical and astronomical treatise on the apparent motions of the stars and planetary paths, written by Claudius Ptolemy ( ).
what is serpens? A constellation of the northern hemisphere. who discovered it? Ptolemy. who was he? A mathematician, astronomer and astrologer. what kind of researches had he carried out? He estimated the Sun was at an average distance of 1,210 Earth radii. has his researches been published ? Yes, "Almagest". how is he associated with music? He wrote "Harmonics", on music theory. what is the former research work based on ? The apparent motions of the stars and planetary paths.
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Almagest [SEP] Introduction
The Almagest is a 2nd-century Greek-language mathematical and astronomical treatise on the apparent motions of the stars and planetary paths, written by Claudius Ptolemy ( ). One of the most influential scientific texts of all time, it canonized a geocentric model of the Universe that was accepted for more than 1200 years from its origin in Hellenistic Alexandria, in the medieval Byzantine and Islamic worlds, and in Western Europe through the Middle Ages and early Renaissance until Copernicus. It is also a key source of information about ancient Greek astronomy. Ptolemy set up a public inscription at Canopus, Egypt, in 147 or 148.