USNO Astronomical Applications API
LiveLast verified 28 Sept 2026
Moon phase dates, daily sun and moon rise/set, eclipses, seasons, Julian dates and sidereal time from USNO.
Example request
curl -s 'https://aa.usno.navy.mil/api/moon/phases/date?date=2009-5-3&nump=48'
Free tier, in plain English
No key needed; an optional ID parameter lets USNO count unique users. No request limit is published.
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