#ancient astronomy

• Almagest — A spelling variant used for 'Almagest', the famous mathematical and astronomical treatise written in the 2nd century AD by Claudius Ptolemy in Alexandria. The work represents the ultimate synthesis of ancient Greek astronomy, proposing the geocentric model of the Universe (where the Earth sits unmovable at the center, surrounded by planetary and stellar spheres) that dominated European and Islamic scientific thought for over fourteen centuries until the Copernican revolution.
• Antinous — The original Latin form of the name Antinou; a term used in international archaeology to designate the sculptural typology associated with Hadrian's favorite. It also names a historical constellation located south of Aquila, introduced by Hadrian into the star catalog and used in European astronomy until it was officially discarded by the International Astronomical Union.
• Counter-Earth — A hypothetical celestial body or imaginary planet symmetrically located on the same orbit as the Earth, but permanently situated in a diametrically opposite position behind the Sun, thus remaining invisible to terrestrial observers. This structural concept was initially introduced in ancient astronomy by the Pythagorean Philolaos of Crotona to explain eclipses and complete the number of sacred cosmic spheres.
• Aristarchus — A historical proper name borne by prominent figures of Antiquity, the most famous being Aristarchus of Samos, the Greek astronomer who first formulated the heliocentric model of the Solar System, placing the Sun at the center. In a philological sense, it also refers to Aristarchus of Samothrace, a literary critic famous for his rigorous editing of Homeric epics, his name becoming a common noun synonymous with a severe but highly competent critic.