# Civil, Nautical and Astronomical Twilight | SunCast

Learn the difference between civil, nautical, and astronomical twilight, including sun angle ranges and practical uses for each phase.

Canonical HTML: https://suncastapp.com/learn/civil-nautical-astronomical-twilight
Last updated: 2026-07-14

Author: [Peter Szucs](https://suncastapp.com/about/peter-szucs)

Primary prompt: what are civil nautical and astronomical twilight

## Short Answer

Civil, nautical, and astronomical twilight are phases of daylight before sunrise or after sunset. Civil twilight happens when the sun is 0 to 6 degrees below the horizon, nautical twilight from 6 to 12 degrees, and astronomical twilight from 12 to 18 degrees.

## Twilight phases by sun angle
- **Civil twilight**: Sun is 0 to 6 degrees below the horizon.
- **Nautical twilight**: Sun is 6 to 12 degrees below the horizon.
- **Astronomical twilight**: Sun is 12 to 18 degrees below the horizon.
- **Night**: Sun is more than 18 degrees below the horizon.

## Civil twilight

Civil twilight is the brightest twilight phase. The sky still has enough light for many outdoor activities, although artificial light may be needed depending on the place and weather.

For photographers, civil twilight can keep detail in the sky while city lights or window lights begin to show.

## Nautical twilight

Nautical twilight is darker. The horizon can still be visible in open areas, but the scene has a stronger evening or pre-dawn feel.

This phase can be useful for seascapes, skyline photos, and routes where you want to understand how quickly light is fading.

## Astronomical twilight

Astronomical twilight is the darkest twilight phase before full night. The remaining sunlight is faint, and the sky is closer to true darkness.

It matters for stargazing, night photography, and knowing when sky glow from the sun is mostly gone.

## Practical uses
- **Walking or hiking**: Civil twilight is often the most useful planning phase because there is still meaningful ambient light.
- **Coastal or skyline photography**: Nautical twilight can balance a darker sky with visible horizon shape and artificial lights.
- **Night sky planning**: Astronomical twilight helps estimate when the sky is dark enough for stars or low-light work.

## Limits

Twilight angle ranges describe the sun position, but clouds, haze, city light, terrain, and latitude can change how bright the sky appears.

## Check It in SunCast

Need local twilight times? SunCast shows civil, nautical, and astronomical twilight alongside sunrise, sunset, golden hour, and blue hour.

- [Download SunCast](https://apps.apple.com/app/id6757196901)

- [Check sun times](https://suncastapp.com/tools/sun-times)

## FAQ

### Which twilight phase is brightest?

Civil twilight is the brightest phase because the sun is closest to the horizon.

### When does night begin?

Night begins after astronomical twilight, when the sun is more than 18 degrees below the horizon.

### Is blue hour the same as twilight?

Blue hour happens during part of twilight, but it is a photography term rather than one of the formal twilight angle ranges.

## Related SunCast Pages
- [Sun times calculator](https://suncastapp.com/tools/sun-times)
- [Golden hour vs blue hour](https://suncastapp.com/learn/golden-hour-vs-blue-hour)
- [What is blue hour?](https://suncastapp.com/blog/what-is-blue-hour)
- [All SunCast learn pages](https://suncastapp.com/learn)