What does the GoChronos Sun & Moon tool calculate?

The tool calculates precise sunrise, sunset, solar noon, civil twilight, nautical twilight and astronomical twilight times, plus moon phase name, illumination percentage, and moonrise/moonset times — all for any location and any date.

What is civil twilight?

Civil twilight is the period just before sunrise and just after sunset when the sun is between 0° and 6° below the horizon. There is enough natural light for most outdoor activities without artificial lighting.

How is sunrise calculated?

Sunrise is calculated from the sun's declination (which varies through the year due to Earth's axial tilt), the observer's latitude and longitude, and standard atmospheric refraction at the horizon (approximately 0.833°). GoChronos uses the SunCalc library, accurate to within 1 minute.

What are the 8 moon phases?

New Moon, Waxing Crescent, First Quarter, Waxing Gibbous, Full Moon, Waning Gibbous, Last Quarter and Waning Crescent. The cycle repeats approximately every 29.53 days (one synodic month).

How long is a lunar cycle?

One complete lunar cycle (new moon to new moon) is approximately 29.53 days, known as a synodic month. This differs from the orbital period of 27.32 days because Earth is also moving around the Sun.

Is the Sun & Moon tool free?

Yes. Free on GoChronos, works offline.

Sun & Moon — Sunrise, Sunset & Moon Phase

Precise sunrise, sunset, golden hour and twilight times plus moon phase, illumination, moonrise and moonset for any city.