Red Twilight and White Twilight
How twilight relates to Fajr and Isha calculation and method differences.
Twilight describes changes in sky brightness before sunrise and after sunset. Some Fajr and Isha discussions relate to how this twilight is defined and calculated.
Different twilight angles or method settings explain why Fajr may be earlier or Isha later in one timetable than another, especially at higher latitudes.
Effect on Prayer Times
Fajr and Isha are more sensitive to twilight differences than Dhuhr or Maghrib, because their signs are linked to gradual light rather than a sharper event like sunset.
That is why the method appears on city pages and links to Fajr, Isha, and accuracy guidance.
Sources and Methodology
These links explain the general source or method behind the page. They do not turn the page into a personal ruling, and local calendars or authorities still take precedence when they differ.
- NOAA Solar Calculation Details - General solar-position and sunrise/sunset calculation reference.
- U.S. Naval Observatory Solar Coordinates - Approximate solar-coordinate method used in astronomical calculations.
- PrayTimes Calculation Notes - Practical reference for Fajr/Isha angles and common prayer-time methods.
- World Salah Times methodology and accuracy limits - Internal explanation of calculated times and their limits.