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Format of the Data File

  1. JD: The Julian Date of the observation.
  2. Magnitude: The magnitude estimate of the observation. A < sign means it was a null observation "fainter than" the magnitude given.
  3. Uncertainty: Uncertainty (error) of the observation as submitted by the observer
  4. HQuncertainty: Uncertainty (error) of the observation as calculated by AAVSO Headquarters

Software that exports AAVSO format

Exports to Visual Format:

Exports to Extended Format:

AAVSO File Format Specifications

This Official AAVSO file report format was released on January 15, 2008.

Files of observations uploaded to the AAVSO via the WebObs File Upload tool must be formatted in the Official AAVSO Format. Visit our page on Software that exports to AAVSO format to help format your observations.

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