PVO Ion Mass Spectrometer high-resolution data are stored in single-orbit ASCII files. All of the data files have the same internal structure, which is described by the single format file OIMSDATA.FMT. File structure characteristics which may vary from file to file (# of records, start/stop time, etc.) are described in the individual PDS label files (*.LBL). Columns in all data files: ======================================================= name type description ------------------------------------------------------- PVO TIME char Date and time in format YYDOY FSEC, where YY is the year, DOY is the day-of-year & FSEC is the decimal second-of-day DWELL int Dwell time (time interval between samples, msec) DWELL = (TIME - UT)*1000/(n-1) BITS int Telemetry bit rate LAT float Venusian Latitude LON float Venusian Longitude ALT float Altitude SZA float Solar Zenith Angle SHA float Solar Hour Angle
MASS1 int Mass of Sample 1 DEN1 float Number density of Sample 1 MASS2 int Mass of Sample 2 DEN2 float Number density of Sample 2 . . . . . . . . . MASS55 int Mass of Sample 55 DEN55 float Number density of Sample 55 The values 999 and 9.9999e+04 are the missing data values for mass and density respectively. The value 99999.999 is the missing data value for the second-of-day part of the time column. Negative values in a density column indicate flagged (unreliable) data values. Data Files (.TAB extension) The high-resolution data files on this disk are ASCII table files, each having 118 columns and record length 953 bytes. Information about the individual files (number of records, start and stop times, etc.) can be obtained from the PDS label file accompanying each *.TAB file. This label file has the same filename as the data file but with .TAB replaced by .LBL. List of data files: ============================================================================ Name Records Cols Len Start Stop ---------------------------------------------------------------------------- ORB2511 376 118 953 1985-10-20T22:26:32.984Z 1985-10-20T23:12:12.000Z ORB2512 127 118 953 1985-10-21T22:40:32.047Z 1985-10-21T23:11:24.055Z ORB2513 299 118 953 1985-10-22T22:34:56.906Z 1985-10-22T23:06:26.102Z ORB2515 174 118 953 1985-10-24T22:27:06.719Z 1985-10-24T23:18:18.727Z ORB2516 338 118 953 1985-10-25T22:27:18.273Z 1985-10-25T23:27:17.289Z ORB2517 208 118 953 1985-10-26T22:28:03.820Z 1985-10-26T23:27:31.836Z ORB2518 455 118 953 1985-10-27T22:28:08.469Z 1985-10-27T23:27:58.883Z ORB2519 208 118 953 1985-10-28T22:28:29.422Z 1985-10-28T23:27:58.438Z ORB2520 16 118 953 1985-10-29T22:41:31.289Z 1985-10-29T22:43:05.742Z ORB2523 338 118 953 1985-11-01T22:29:17.219Z 1985-11-01T23:11:46.820Z ORB2524 212 118 953 1985-11-02T22:29:43.172Z 1985-11-02T23:29:26.188Z ORB2525 458 118 953 1985-11-03T22:30:05.312Z 1985-11-03T23:29:49.727Z ORB2527 304 118 953 1985-11-05T22:43:57.125Z 1985-11-05T23:17:21.242Z ORB2529 156 118 953 1985-11-07T22:47:57.969Z 1985-11-07T23:20:43.969Z ORB2530 462 118 953 1985-11-08T22:31:31.102Z 1985-11-08T23:31:30.523Z ORB2531 154 118 953 1985-11-09T22:46:20.070Z 1985-11-09T23:18:41.078Z ORB2532 288 118 953 1985-11-10T22:45:51.945Z 1985-11-10T23:19:02.250Z ORB2533 68 118 953 1985-11-11T22:32:43.203Z 1985-11-11T23:32:32.219Z ORB2534 305 118 953 1985-11-12T22:47:14.070Z 1985-11-12T23:19:41.078Z ORB2536 190 118 953 1985-11-14T22:33:56.891Z 1985-11-14T23:21:22.906Z ORB2537 299 118 953 1985-11-15T22:48:11.750Z 1985-11-15T23:21:04.336Z ORB2538 111 118 953 1985-11-16T22:34:46.008Z 1985-11-16T23:34:36.031Z ORB2539 290 118 953 1985-11-17T22:48:55.875Z 1985-11-17T23:21:53.586Z ORB2540 214 118 953 1985-11-18T22:35:35.102Z 1985-11-18T23:35:01.117Z ORB2541 283 118 953 1985-11-19T22:49:56.961Z 1985-11-19T23:19:33.398Z ORB2543 198 118 953 1985-11-21T22:36:48.758Z 1985-11-21T23:36:15.781Z ORB2546 319 118 953 1985-11-24T22:51:17.703Z 1985-11-24T23:24:47.008Z ORB2547 42 118 953 1985-11-25T22:43:04.945Z 1985-11-25T22:57:07.953Z ORB2548 315 118 953 1985-11-26T22:52:23.797Z 1985-11-26T23:25:21.648Z ORB2550 213 118 953 1985-11-28T22:39:26.594Z 1985-11-28T23:39:19.609Z ORB2551 318 118 953 1985-11-29T22:53:15.438Z 1985-11-29T23:26:32.680Z ORB2552 210 118 953 1985-11-30T22:40:13.695Z 1985-11-30T23:39:57.711Z ORB2553 208 118 953 1985-12-01T23:06:33.242Z 1985-12-01T23:28:23.250Z ORB2556 172 118 953 1985-12-04T22:41:42.859Z 1985-12-04T23:41:26.875Z ORB2557 208 118 953 1985-12-05T22:42:27.391Z 1985-12-05T23:38:52.406Z ORB2559 157 118 953 1985-12-07T22:55:44.453Z 1985-12-07T23:28:30.461Z ORB2560 286 118 953 1985-12-08T22:56:59.281Z 1985-12-08T23:29:12.930Z ORB2561 444 118 953 1985-12-09T22:43:51.516Z 1985-12-09T23:43:33.523Z ORB2562 261 118 953 1985-12-10T23:00:31.344Z 1985-12-10T23:29:16.797Z ORB2563 138 118 953 1985-12-11T22:57:33.570Z 1985-12-11T23:29:54.578Z ORB2564 197 118 953 1985-12-12T22:44:48.086Z 1985-12-12T23:44:38.102Z ORB2566 157 118 953 1985-12-14T22:58:49.141Z 1985-12-14T23:31:48.141Z ORB2567 308 118 953 1985-12-15T22:59:47.961Z 1985-12-15T23:32:26.969Z ORB2568 63 118 953 1985-12-16T22:59:11.188Z 1985-12-16T23:12:12.195Z ORB2569 299 118 953 1985-12-17T22:59:44.008Z 1985-12-17T23:32:55.016Z ORB2571 198 118 953 1985-12-19T22:46:51.758Z 1985-12-19T23:46:42.773Z ORB2573 181 118 953 1985-12-21T22:47:28.797Z 1985-12-21T23:47:03.812Z ORB2574 15 118 953 1985-12-22T23:10:24.336Z 1985-12-22T23:21:13.336Z ORB2575 131 118 953 1985-12-23T22:50:04.836Z 1985-12-23T23:46:47.852Z Catalog Files (.CAT extension) Catalog data, which includes instrument, dataset, mission and spacecraft descriptions, can be found in the *.CAT files in the CATALOG directory on this disk.