The study of the two academics, introduced by Professor Vasilios Barbani, Professor of Astronomy at the University of Thessaloniki, addresses the concept of time from an astronomical and historical-philosophical perspective, presenting to us the gigantic efforts made by humans since ancient times to understand it. After all, time is an endless field of scientific and philosophical quests. The authors, developing their subject with simplicity, fluency, scientific clarity, and precision, make it perhaps unique in its kind and create a rich source of knowledge both in terms of historical and philosophical evolution of human ideas about time. But what is time? What is its meaning, which forms the basis of human life and social relationships? Is it what clocks and calendars present or something deeper and more substantial? We all say that time passes. But where does it go? Is time measurable? The question has occupied mystics, philosophers, and astronomers for centuries. However, the answer stubbornly lies in its philosophical and metaphysical concept. Through the pages of the study of the two academics, it becomes apparent that the global history of time and its measurement methods have accompanied the history and development of human civilization. The pages of the book are adorned with beautiful photographs, while a multitude of figures assists the reader in understanding the corresponding text. The astronomical knowledge provided in the Appendix of the book is very useful, as well as the rich Greek and foreign bibliography, which is presented at the end of the book and can be used by any reader who wishes to further enrich their knowledge. "Measuring timeless time - time in Astronomy" is addressed and dedicated to those who are interested in knowing and understanding the concept of timeless time, as well as to amateur astronomers in order to understand the concept of relative measurable time. Additionally, the book of the two academics is a significant challenge of knowledge, addressed not only to the "measurers" but also to the "mystics" of timeless time, the Governor of the Universe!