00readme_sec.txt Updated 16 July 2019 This directory contains the following sub-directories: SEC_Jackson_src Source files for Jackson ionogram inversion and worldmap ephemeris programs, modified to compile with gfortran under Linux. Should be substantially the same results as the original versions. SEC_documentation see 00readme.txt file in the directory for more information SEC_images_JPG_PNG see 00readme.txt file in the directory for more information SEC_ionogram_tar Tar files for each ISIS-2 EDP, containing the data files used to generate the EDPs. See 00README.txt in the directory for details. sec_ne_profile_cdf ISIS-2 topside EDPs in CDF form for the years 1972 and 1973. See 00README.txt in the directory for details. It also contains the text file Submission_Notes_2019.txt.