Muslims perform the prayers facing towards the correct qibla direction would be the only one of the practical issues in linking theoretical studies with practice. The concept of facing towards the Kaaba in Mecca during the prayers has long been the source of controversy among the muslim communities to not only in poor and developing countries but also in developed countries. The aims of this study were to analyse the geodetic azimuths of qibla calculated using three different models of the Earth. The use of ellipsoidal model of the Earth could be the best method for determining the accurate direction of Kaaba from anywhere on the Earth’s surface. A muslim cannot direct himself towards the qibla correctly if he cannot see the Kaaba due to setting out process and certain motions during the prayer this can significantly shift the qibla direction from the actual position of the Kaaba. The requirement of muslim prayed facing towards the Kaaba is more as spiritual prerequisite rather than physical evidence.

Sky brightness data have been widely used to document the light pollution and to localise the direction of the sun during both dawn and dusk twilight. The use of the most common data analysis techniques of graphical interpretation can give less accurate final results. This study used a Sky Quality Metre to record the brightness of night sky in mag arcsec −2 at Depok city of Indonesia during 26 days for the months of June and July 2015. Analytical technique of thirddegree polynomial was established to predict dawn astronomical twilight and provides a good fit to the experimental data. The modelling results have been experimentally verified that astronomical twilight in the morning at Depok city with its environment begins when the sun is at the position of −14°± 0.6 below the eastern horizon and ends at sunrise. In conclusion, the Muslim communities of Indonesia begin their dawn prayer 6°too early and have been found to calculate the true dawn incorrectly when the centre of the sun is at a depression angle of −20°b elow the horizon. ARTICLE HISTORY

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This paper summarizes ISRN’s 3-years research on the occurrence of dawn and dusk to mark the timings of the Fajr and Isha prayers. We acquired the astronomical data not only in Indonesia but also in Malaysia, the US, Egypt, and Turkey. It will be an attempt to compile a global twilight pattern in the future. The main instrument used is a Sky Quality Meter (SQM) that records the sky brightness data. For quality assurance, ISRN-UHAMKA employed dozens of imaging sensors ranging from an All Sky Camera, different types of DSLR, and gadget cameras. From hundreds of astronomical data, we have collected; it seems that the occurrence of the real twilight to mark the Fajr prayer throughout the world is the same. That is when the sun is at its depression angle of around 120-130. Likewise, the dusk to mark the end of the Maghrib prayer also occurs when the sun is at a solar depression angle around 120-130. Meanwhile, Muslims in the world use different solar depression angles ranging from -150 to -200.fields.