Cleomedes

Cleomedes ( Κλεoμήδης ) is the author of an astronomical treatise in Greek language. The font is titled About the circular motion of the heavenly bodies, and includes two books ( in the ancient sense). This work is for us the only source of information about the author, as no parallel traditions have been preserved over Cleomedes.

Substantive evidence and linguistic criteria make it likely that the treatise of Cleomedes has been written in the middle of the second century AD. The work probably does not represent the current state of the former astronomy, but may have served as a kind of compendium of the ancient " academia ".

Content noteworthy are four details:

• In the writing of the Cleomedes contains a detailed description of the procedures by which Eratosthenes and Posidonius have calculated the earth's circumference ( 1.10 ( § 52 et seq. ) ).
• The treatise contains a summary of arguments for the sphericity of the earth (1.8 ( § 40 et seq. ) ).
• Cleomedes reported a lunar eclipse, the sun and moon were at the same time still on the horizon and puts this down to atmospheric radiation refraction, which is considered one of the first traditions of astronomical refraction. ( 2.6 )
• The author polemic in one place unusually heavy against Epicurus - not only against his doctrine, but also against his linguistic style (2.1 ( § 86ff ). ). Cleomedes Thus does as a staunch follower of the Stoic doctrine.