WAKTU SUBUH: Integrasi Agama dan Sains

The visibility of the new crescent (hilal) remains one of the most challenging issues in determining the beginning of the Hijri months. The long-standing debate between rukyat (direct observation) and hisab (astronomical calculation) often centers on a fundamental question: why is the hilal so difficult to observe, especially under the strong brightness of twilight (syafaq)? Visibilitas Hilal by Dr. Sakirman, M.S.I. offers a scientific exploration of this problem through an integrated approach combining rukyatul hilal studies, the physical characteristics of the crescent, and the photometric behavior of twilight sky brightness. By examining the interaction between light contrast, the physical properties of the crescent, and atmospheric conditions, this book provides a comprehensive explanation of the factors that determine the success or failure of hilal observations. Through theoretical discussion, analysis of observational data, and an in-depth look at various observing instruments such as telescopes, cameras, and photometric devices, this book presents a holistic picture of how the crescent actually appears in real observational conditions. Its multidisciplinary perspective makes it highly relevant for hilal observers, astronomers, Islamic astronomy experts, as well as academics, students, and the wider public interested in understanding the visibility of the crescent from a scientific viewpoint. Supported by extensive research and field experience in hilal observation programs, Visibilitas Hilal offers an important contribution to the body of literature on Islamic astronomy in Indonesia. It not only provides new insights but also opens space for scientific dialogue toward strengthening the methodology of Hijri calendrical determination in the future.