Foreword by Professor Emeritus of the University of Athens Maro K. Papathanasiou .

From the rich written work of the father of Astronomy, Hipparchus, only the "Explanation of the Phenomena of Aratus and Eudoxus book 3" survives. It is a treatise consisting of two main parts. The first part is a commentary on the lost works:

* Eudoxou : "Phenomena",

* Eudoxou : "Enoptron",

* Attalus of Rhodium : "Comments to Araton".

and of Aratos ' astronomical poem "Phenomena".

The second part refers to information about the constellations of the two hemispheres of the celestial sphere and the zodiacal zone (sunrises, sunsets, meridians, sunrises and sunsets). It also refers to the 24 hour intervals defined by the 24 meridians.