Digitized Auroral Data

Description

This data collection contains the results from microdensitometer scans of the auroral and lower atmosphere emission photography contained in data sets SPIO-00031 (Black & White Auroral Photography) and SPIO-00074 (Color Auroral Photography). Each record contains one scan line, and a file mark is placed at the end of each complete frame scan. Four file marks indicate the end of the recording on a tape. An identification label at the beginning of each record gives the magnetic tape number and file number, date of tape recording, ID of film frame, frame number, number of steps per scan line, number of scan lines, aperture size in micrometers, and speed of the scan. Included in the record are the X and Y coordinates, the distance between density readings, and the density (or transmission) value. Details of the scan technique, the calibration procedures, and an analysis and interpretation of several auroral frames are contained in the document distributed with the data. Also see Applied Optics, v. 16, no. 4, pp. 983-992, April 1977. For more information on this data set, contact Dr. Donald Packer, 1623 Fran Hammond Parkway, Alexandria, VA 22302.