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Dates of Primary Phases of the Moon

This data service calculates the primary phases of the moon for years between 1700 and 2100. Specify the year, the number of phases, and the data format in the form below. Then press the "Get Data" button to obtain a table displaying the dates of the primary phases of the Moon arranged either by time or by phase.

Format: YYYY-MM-DD

Number of Phases

Data format Displayed by phase     Displayed by time

Notes

Definitions

For definitions of the phases, see the explanation of Phases of the Moon and Percent of the Moon Illuminated in the Astronomical Information Center. In addition, the explanation of Crescent Moon Visibility discusses the waxing crescent phase.

Time Format

In the output table, the date indicates the day, hour, minute, respectively, of Universal Time. To convert the times given to local time, see the U.S. Time Zones explanation or the World Time Zone Map in the Astronomical Information Center.

Computing the Phase for a Particular Day

Several of our Data Services will compute the fraction of the Moon illuminated for particular days. The Fraction of the Moon Illuminated service provides values for each day of a calendar year. The Complete Sun and Moon Data for One Day reports the percent illuminated for a particular day along with location-specific data.

Application Programming Interface

This data service uses one of our Application Programming Interfaces (APIs). The API returns data in JavaScript Object Notation (JSON) format for users who wish to manipulate data into a customized format. For more information on the API, please see the documentation page.