Using Advanced Astronomical Techniques and a Machine-Learning System

The University of Sharjah’s Sharjah Space and Astronomy Hub (SSAH) has announced the results of its astronomical calculations concerning the visibility of the crescent moon marking the beginning of Rabi’ al-Thani 1448 AH on the evening of Friday, September 11, 2026. The calculations indicate that the crescent will not be visible after sunset, either with the naked eye or through a telescope. However, it may be possible to detect it before sunset using advanced astronomical imaging techniques, under limited observing conditions.

The findings are part of the SSAH'a ongoing efforts to study lunar crescents, develop methods for analyzing their visibility, and use modern observation technologies and artificial intelligence to provide accurate astronomical data. Drawing on modern technologies and artificial intelligence in space and astronomy research, SSAH conducted a test using a machine-learning system developed at the hub to analyze the possibility of sighting the crescent based on astronomical data and observing conditions. The test results classified the Rabi’ al-Thani crescent as “not visible” to the naked eye or with a telescope, in accordance with astronomical calculations of the crescent’s observing conditions on that day.

According to astronomical calculations, the Moon will reach the moment of central conjunction, or new moon, at 7:27 a.m. on Friday, September 11, 2026. Surface conjunction for the city of Sharjah will occur at 5:38 a.m. UAE local time, corresponding to 29 Rabi’ al-Awwal 1448 AH.

At sunset, the surface age of the crescent will be approximately 12 hours and 50 minutes. It will remain above the horizon for no more than six minutes after sunset, while its altitude above the horizon will be 1 degree and 13 minutes. Its angular separation from the Sun will reach 5 degrees and 57 minutes. These indicators make observing the crescent under these conditions difficult.

SSAH noted that conditions for observing the Rabi’ al-Thani crescent will improve significantly on the evening of Saturday, September 12, when it is expected to become easier to observe with the naked eye.

Based on astronomical calculations, countries that use astronomical calculations to determine the beginning of the month are expected to begin Rabi’ al-Thani on Saturday, September 12. Countries that rely on visual observation, or on visual observation informed by astronomical calculations, are expected to begin the month on Sunday, September 13.