Clime
← Back to Blog
Guides

Understanding Twilight Times: A Beginner's Guide

June 18, 2026 · The Clime Team
Understanding Twilight Times: A Beginner's Guide

Twilight is the period between day and night when the sun is below the horizon, yet its light scatters through the atmosphere, illuminating the sky. This transitional phase is divided into three distinct stages: civil, nautical, and astronomical twilight.

What Are the Phases of Twilight?

Twilight is categorized based on the sun's position below the horizon:

  • Civil Twilight: Occurs when the sun is between 0 and 6 degrees below the horizon. During this phase, there is enough natural light for most outdoor activities without artificial illumination.

  • Nautical Twilight: Happens when the sun is between 6 and 12 degrees below the horizon. This phase is significant for sailors, as the horizon is still visible at sea, allowing for navigation using the stars.

  • Astronomical Twilight: Begins when the sun is between 12 and 18 degrees below the horizon. This is the period when the sky is dark enough for astronomers to observe celestial objects without interference from sunlight.

Why Are Twilight Times Important?

Understanding twilight times is essential for various activities:

  • Photography: The soft, diffused light during twilight provides optimal conditions for capturing landscapes and cityscapes.

  • Stargazing: Astronomical twilight offers the darkest skies, ideal for observing stars and other celestial bodies.

  • Navigation: For sailors and hikers, knowing twilight times aids in planning safe travel during low-light conditions.

How to Calculate Twilight Times

Calculating twilight times involves determining the times when the sun reaches specific angles below the horizon. This can be done using online tools or astronomical calculators. For instance, the U.S. Naval Observatory provides detailed tables of twilight times for various locations. Additionally, websites like TimeandDate.com offer daily sun and moon times, including twilight phases, for cities across the United States.

Twilight Times in the United States

Twilight times vary depending on the date and geographic location. For example, in Compton, California, on June 18, 2026, the twilight phases are as follows:

  • Morning Civil Twilight: 5:13 AM – 5:42 AM

  • Morning Nautical Twilight: 4:38 AM – 5:13 AM

  • Morning Astronomical Twilight: 3:59 AM – 4:38 AM

  • Evening Civil Twilight: 8:00 PM – 8:29 PM

  • Evening Nautical Twilight: 8:29 PM – 9:04 PM

  • Evening Astronomical Twilight: 9:04 PM – 9:43 PM

These times are specific to Compton, California, and will differ in other parts of the United States. For accurate twilight times in your area, consult local astronomical resources or online tools.

Tips for Observing Twilight

  • Plan Ahead: Check twilight times before heading out to ensure optimal lighting conditions for your activities.

  • Safety First: While twilight provides some natural light, it's essential to have appropriate lighting if you're in areas with limited visibility.

  • Embrace the Moment: Twilight offers unique lighting and atmospheric conditions, making it a perfect time for photography, reflection, or simply enjoying the changing sky.

By understanding and utilizing twilight times, you can enhance your outdoor experiences, whether it's capturing the perfect photograph, observing the night sky, or navigating safely during low-light conditions.

Frequently Asked Questions