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Application Programming Interface Changelog

Astronomical Applications API v4.0.1

30 September 2022

  • "isCorrected" property that indicates whether to display altitude corrections for a celestial object has been added to "altitude_corrections" structure in Celestial Navigation Data for Assumed Position and Time.
  • Increased precision for values in "almanac_data" and "altitude_corrections" in Celestial Navigation Data for Assumed Position and Time. Note: Accuracy is only guaranteed to values displayed on webpage.

Astronomical Applications API v4.0.0

8 July 2021

  • Date Format changed from mm/dd/yyyy to yyyy-mm-dd.

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Astronomical Applications API v3.0

30 April 2020

  • Complete Sun and Moon Data for One Day is now is GeoJSON format.
  • Solar Eclipse Computer is now in GeoJSON format.
  • The date/time parameters "today", "tomorrow", "now", "yesterday", "midnight", and "noon" have been removed.
  • The coordinate tags "N", "S", "E", and "W" have been removed.
  • URLs for querying many of the APIs have changed.
  • The Celestial Navigation Data for Assumed Position and Time calculator is now API-enabled.

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API v2.2

20 November 2018

  • The APIs are now being served over https.

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API v2.1

3 January 2018

  • The Earth's Seasons and Apsides page has been converted to an API-based data service. Information on this data service has been added to the API documentation page.

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API v2.0

30 December 2016

  • The Julian Date Converter data service has been converted to an API. Information on this data service has been added to the API documentation page.
  • The Sidereal Time data service has been converted to an API. Information on this data service has been added to the API documentation page.
  • The First Day of Passover data service has been changed to Selected Jewish Observances and now includes 5 additional Jewish observances. Information on this data service has been updated on the API documentation page.
  • The Dates of Easter and Ash Wednesday data service has been changed to Selected Christian Observances and now includes 6 additional Christian observances. Information on this data service has been updated on the API documentation page.
  • The Dates of Islamic New Year and Ramadân data service has been changed to Selected Islamic Observances and now includes one additional Islamic observance. Information on this data service has been updated on the API documentation page.

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API v1.3

7 June 2016

  • The Dates of Islamic New Year and Ramadân data service has been created. Information on this data service has been added to the API documentation page.
  • The First Day of Passover data service has been created. Information on this data service has been added to the API documentation page.

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API v1.2

11 March 2016

  • The Dates of Ash Wednesday and Easter data service has been converted to an API. Information on this service has been added to the API documentation page.
  • Year keyword was added for use in the Easter and forthcoming APIs.

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API v1.1

14 December 2015

  • The Solar Eclipse Computer data service has been converted to an API. Information on this service has been added to the API documentation page.
  • Height and Format keywords were added for use in the Solar Eclipse Computer and forthcoming APIs.

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API v1.0.1

12 August 2015

  • The day of the week was added to the Complete Sun and Moon Data for One Day data service.
  • The output format for non-imagery APIs was changed from text/html to application/json.

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API v1.0

The initial API release included four data services: Day and Night Across the Earth, Apparent Disk of a Solar System Object, Phases of the Moon, and Complete Sun and Moon Data for One Day.

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