Short answers, pulled from the story.
Science in classical antiquity covers the period from the 8th century BC, beginning with Archaic Greece, through the 6th century AD. It is geographically limited to the Greco-Roman West, the Mediterranean basin, and the Ancient Near East.
The most widely known figures include Hippocrates, Aristotle, Euclid, Archimedes, Hipparchus, Galen, and Ptolemy. Their works spanned mathematics, cosmology, medicine, and physics, and spread through the Eastern, Islamic, and Latin worlds.
Aristarchus of Samos (310-230 BC) proposed the first known heliocentric model, placing the Sun at the center of the known universe with the Earth revolving around it once a year and rotating on its axis once a day. The model found few adherents in antiquity but later influenced Nicolaus Copernicus.
The Antikythera mechanism (150-100 BC) is a 37-gear mechanical computer built during the Hellenistic age that calculated the motions of the Sun and Moon and may have tracked the other five planets known to the ancients. It also predicted lunar and solar eclipses based on astronomical periods believed to have been learned from the Babylonians.
Galen, active in the 2nd century AD, produced around 100 surviving works filling 22 volumes of modern text. He demonstrated that living arteries contain blood rather than air, and his two anatomical works, On anatomical procedure and On the uses of the parts of the body of man, remained the authoritative foundation of medicine for 1300 years until challenged by Vesalius and Harvey in the 16th century.
Euclid (325-265 BC) authored the Elements, a series of books establishing a canon of geometry and elementary number theory. The Elements served as the main textbook for the teaching of theoretical mathematics until the early 20th century.