Pseudo dawn and true dawn observations by naked eye in Egypt

Zodiac Light Detection Based on Sky Quality Meter (Sqm) Data: Preliminary Study

“…If the initial appearance of dawn in Labuan Bajo and Mombhul Beach with SQM observations is averaged, then the h value is -19.14 o . The results of our study differ from those of Semeida et al (2018) which states that the appearance of the zodiacal light is when h = -19.71 o , while the end of the zodiacal light is when h = -14.59 o .…”

“…If the initial appearance of dawn in Labuan Bajo and Mombhul Beach with SQM observations is averaged, then the value of h is -19.14 o . The results of our study differ from those ofSemeida et al (2018) which states that the appearance of the zodiacal light is when h = -19.71 o , while the end of the zodiacal light is when h = -14.59 o . 3 By looking at the results of the dawn twilight light curve pattern and the appearance of the zodiacal light, it shows that light pollution, weather, and the position of the tool in data collection greatly affect the early appearance of dawn.…”

The Urgency and Contribution of Information Technology in Verifying the Beginning of Shubuh Time and the Height of Hilal Determining the Beginning of the Hijri Month

“…The results of dawn observation with ordinary eyes depend on the physical and mental readiness of the observer and the results will be subjective. [32] Observation of objects that are long enough will easily cause saturation, resulting in an optical illusion, especially when physical conditions are less fit. This will be very different from observation using tools.…”