What is Nightfall - ilallayl:

• For those who fast, especially during Ramadan, breaking the fast is traditionally done at the onset of true night. Nightfall - ilallayl App uses Astronomical Twilight to detect the exact time of true night based on your area, and by waiting until the end of astronomical twilight, Nightfall - ilallayl App ensures that all residual sunlight has disappeared, avoiding any doubt and allowing you to break your fast at the exact, proper time.

• On the other end, Nightfall - ilallayl App ensures you begin fasting at the exact right moment by relying on Nautical twilight—the phase when the sun is 6–12 degrees below the horizon. During this time, the first faint crepuscular rays (delicate sunbeams at dawn) become visible, signaling that sunlight has fully vanished. These rays act as a natural marker, confirming it’s time to fast. To eliminate guesswork, the app does two things:

1. It scientifically tracks the precise start of nautical twilight, ensuring crepuscular rays are unmistakably clear.

2. It accounts for regions where dawn lasts unusually long (e.g., Norway or Alaska), avoiding human error or local inconsistencies.

• By combining celestial science with real-world adaptability, Nightfall - ilallayl guarantees you fast confidently, free from doubt.

The Different Phases After Sunset

• Sunset - The sun disappears below the horizon

• Civil Twilight: Enough light for outdoor activities.

• Nautical Twilight: Horizon details fade.

• Astronomical Twilight: Sky appears dark to casual observers

• End of Astronomical Twilight: Sky is completely dark, marking true night (Nightfall - ilallayl Time).
  
            Sun (at sunset)

 Horizon *___________

           \  

             \

               \ <-- Sun's position moves further down 

                 \

                   \           <-- Civil Twilight

                     \ (sun 0°→6° below horizon) 

                       \       <-- Nautical Twilight

                         \ (sun 6°→12° below horizon)

                           \ <-- Astronomical Twilight

                             \ (sun 12°→18° below horizon)

                               \ <-- True Night (Nightfall - ilallayl Time)

                                 \ (sun 18° below horizon)

Astronomical Twilight End (True Night) Explained:

Astronomical twilight ends when the sun is more than 18° below the horizon, meaning no sunlight is visible at all—even a faint glow. This marks when the sky becomes completely dark, signaling the true beginning of the night.

Crepuscular Rays Explained:

Crepuscular rays are those dramatic beams of sunlight that appear to fan out from the sun, often seen streaming through clouds or trees. They're sometimes called "God rays" or "sunbeams" in everyday language.

Why Break the Fast at Nightfall - ilallayl Time:

1. Complete Darkness Interpretation When the Quran mentions fasting "until nightfall" (ila al-layl), some scholars interpret this to mean complete darkness (end of astronomical twilight) rather than just sunset.

2. Caution in Worship Some follow this timing out of religious caution (ihtiyat), ensuring they've fully completed the required fasting period. (”These are the limits set by Allah, so do not exceed them”)

3. Regional Considerations In areas with unusual daylight patterns (like far northern countries during summer), Nightfall - ilallayl provides a clearer boundary.