Question 1

What can this API calculate?

Accepted Answer

Moon phase and illumination for any date, sunrise/sunset and civil, nautical and astronomical twilight for any GPS coordinates, equinoxes and solstices, the zodiac sign for a date, and eclipse calendars.

Question 2

How do I get sunrise and sunset for my location?

Accepted Answer

Call GET /sun/today?lat=X&lon=Y for today, or GET /sun?lat=X&lon=Y&date=YYYY-MM-DD for any date. It returns sunrise, sunset, solar noon, day length and all three twilight phases.

Question 3

Do you rely on any third-party services?

Accepted Answer

No. All results are computed locally from astronomical algorithms (JPL ephemeris–based), so responses are deterministic, dependency-free and returned in milliseconds.

Astronomy and Time

Frequently Asked Questions