Twilight Calculator – Civil, Nautical & Astronomical
Calculate civil, nautical, and astronomical twilight times for any location and date.
How It Works
Twilight occurs when the sun is below the horizon but still illuminates the sky. Civil twilight ends at 6 degrees below, nautical at 12 degrees, and astronomical at 18 degrees.
Formula
Civil: sun 6deg below horizon | Nautical: 12deg | Astronomical: 18deg
Frequently Asked Questions
What is civil twilight?
Civil twilight occurs when the sun is between 0 and 6 degrees below the horizon. There is enough light for outdoor activities without artificial lighting.
What is astronomical twilight?
Astronomical twilight is when the sun is between 12 and 18 degrees below the horizon. After astronomical dusk, the sky is fully dark for astronomical observation.