who is Claudius Holemy?

Answer 1

I think you want Claudius Ptolemy, the Greek astronomer who lived in Alexandria Egypt in the second century. His books Almagest and Tetrabiblios were the authoritative works in astronomy and astrology respectively, for centuries.

His astronomy placed Earth at the center of the universe, and used a complicated system of circles within circles to explain the motions of the planets. Nevertheless, it wasn't until Kepler (in the early 1600's) figured out that planets orbited the sun in elliptical orbits that anyone had a significantly more accurate way to calculate planetary positions.

Answer 2

Claudius Ptolemaeus known in English as Ptolemy, was a Greek-speaking geographer, astronomer, and astrologer who lived in the Hellenistic culture of Roman Egypt. He may have been a Hellenized Egyptian but no description of his family background or physical appearance exists, though it is likely he was born in Egypt.

Ptolemy was the author of several scientific treatises, three of which have been of continuing importance to later Islamic and European science. The first is the astronomical treatise that is now known as the Almagest (in Greek Η μεγάλη Σύνταξις, "The Great Treatise"). The second is the Geography, which is a thorough discussion of the geographic knowledge of the Greco-Roman world. The third is the astrological treatise known as the Tetrabiblos ("Four books") in which he attempted to adapt horoscopic astrology to the Aristotelian natural philosophy of his day.

I hope this is what you meant.