what did he do being an astrologer?
He has written an astrological treatise, "Tetrabiblos".
Ptolemy
His astrological treatise, a work in four parts, is known by the Greek term "Tetrabiblos", or the Latin equivalent "Quadripartitum": "Four Books". Ptolemy's own title is unknown, but may have been the term found in some Greek manuscripts: "Apotelesmatika", roughly meaning "Astrological Outcomes", "Effects" or "Prognostics".

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. when was it published? 2nd-century. how different is his planetary model from the conventional one? It was geocentric and was almost universally accepted until the appearance of simpler heliocentric models during the scientific revolution. who proposed heliocentric model? UNANSWERABLE which country does he belong to? Greece.
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Ptolemy [SEP] Astrology
It speaks in general terms, avoiding illustrations and details of practice. Ptolemy was concerned to defend astrology by defining its limits, compiling astronomical data that he believed was reliable and dismissing practices (such as considering the numerological significance of names) that he believed to be without sound basis.