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 ---------------------------------------------------------------------------- ORB5000 193 118 953 1992-08-14T00:14:04.234Z 1992-08-14T00:52:25.784Z ORB5001 262 118 953 1992-08-15T00:14:04.200Z 1992-08-15T00:52:30.213Z ORB5002 258 118 953 1992-08-16T00:16:19.646Z 1992-08-16T00:52:38.672Z ORB5003 260 118 953 1992-08-17T00:17:51.122Z 1992-08-17T00:52:44.633Z ORB5004 251 118 953 1992-08-18T00:16:01.586Z 1992-08-18T00:52:48.098Z ORB5005 93 118 953 1992-08-19T00:14:47.512Z 1992-08-19T00:52:42.065Z ORB5006 258 118 953 1992-08-20T00:14:52.976Z 1992-08-20T00:52:53.988Z ORB5007 91 118 953 1992-08-21T00:17:44.158Z 1992-08-21T00:52:32.201Z ORB5008 209 118 953 1992-08-21T23:14:02.875Z 1992-08-22T00:53:20.652Z ORB5009 55 118 953 1992-08-23T00:36:00.052Z 1992-08-23T00:53:00.018Z ORB5010 243 118 953 1992-08-24T00:11:03.965Z 1992-08-24T00:53:31.528Z ORB5011 258 118 953 1992-08-25T00:15:38.414Z 1992-08-25T00:53:40.427Z ORB5012 249 118 953 1992-08-26T00:17:21.325Z 1992-08-26T00:53:47.855Z ORB5013 246 118 953 1992-08-27T00:19:12.279Z 1992-08-27T00:53:52.790Z ORB5014 76 118 953 1992-08-28T00:19:20.960Z 1992-08-28T00:27:13.462Z ORB5015 251 118 953 1992-08-29T00:11:58.872Z 1992-08-29T00:54:10.182Z ORB5016 258 118 953 1992-08-30T00:15:49.636Z 1992-08-30T00:54:17.148Z ORB5017 256 118 953 1992-08-31T00:17:29.304Z 1992-08-31T00:54:24.829Z ORB5018 254 118 953 1992-09-01T00:19:52.531Z 1992-09-01T00:54:26.543Z ORB5019 253 118 953 1992-09-02T00:19:51.994Z 1992-09-02T00:54:32.255Z ORB5020 130 118 953 1992-09-03T00:11:50.842Z 1992-09-03T00:54:22.342Z ORB5021 257 118 953 1992-09-04T00:15:57.563Z 1992-09-04T00:54:51.575Z ORB5022 240 118 953 1992-09-05T00:18:54.729Z 1992-09-05T00:54:53.256Z ORB5023 260 118 953 1992-09-06T00:20:09.458Z 1992-09-06T00:54:47.969Z ORB5024 248 118 953 1992-09-07T00:19:41.918Z 1992-09-07T00:54:21.927Z ORB5025 116 118 953 1992-09-08T00:09:50.324Z 1992-09-08T00:53:30.385Z ORB5026 247 118 953 1992-09-09T00:15:18.052Z 1992-09-09T00:52:55.563Z ORB5028 257 118 953 1992-09-11T00:15:17.871Z 1992-09-11T00:51:44.399Z ORB5029 250 118 953 1992-09-12T00:16:25.572Z 1992-09-12T00:50:45.081Z ORB5030 247 118 953 1992-09-13T00:14:38.001Z 1992-09-13T00:49:06.011Z ORB5031 260 118 953 1992-09-14T00:01:57.435Z 1992-09-14T00:45:43.973Z ORB5032 270 118 953 1992-09-15T00:03:46.568Z 1992-09-15T00:42:21.620Z ORB5033 252 118 953 1992-09-16T00:01:58.289Z 1992-09-16T00:36:13.799Z ORB5034 249 118 953 1992-09-16T23:56:50.742Z 1992-09-17T00:31:35.757Z ORB5035 231 118 953 1992-09-17T23:43:12.172Z 1992-09-18T00:25:45.713Z ORB5036 235 118 953 1992-09-18T23:42:00.633Z 1992-09-19T00:19:19.395Z ORB5037 247 118 953 1992-09-19T23:38:18.828Z 1992-09-20T00:14:16.856Z ORB5038 238 118 953 1992-09-20T23:33:18.805Z 1992-09-21T00:08:16.317Z ORB5039 263 118 953 1992-09-21T23:26:59.516Z 1992-09-22T00:01:46.027Z ORB5040 248 118 953 1992-09-22T23:11:23.438Z 1992-09-22T23:53:36.234Z ORB5041 261 118 953 1992-09-23T23:06:23.906Z 1992-09-23T23:44:13.914Z ORB5042 260 118 953 1992-09-24T22:58:55.820Z 1992-09-24T23:35:21.844Z ORB5043 262 118 953 1992-09-25T22:51:31.805Z 1992-09-25T23:26:05.562Z ORB5044 265 118 953 1992-09-26T22:41:26.258Z 1992-09-26T23:15:59.766Z ORB5045 249 118 953 1992-09-27T22:21:37.922Z 1992-09-27T23:03:50.977Z ORB5046 260 118 953 1992-09-28T22:12:51.148Z 1992-09-28T22:51:02.164Z ORB5047 264 118 953 1992-09-29T22:02:13.578Z 1992-09-29T22:38:33.117Z ORB5048 259 118 953 1992-09-30T21:51:20.312Z 1992-09-30T22:25:47.820Z ORB5049 255 118 953 1992-10-01T21:37:37.766Z 1992-10-01T22:12:15.781Z ORB5050 190 118 953 1992-10-02T21:12:53.688Z 1992-10-02T21:55:17.727Z ORB5051 262 118 953 1992-10-03T21:01:08.391Z 1992-10-03T21:39:09.406Z ORB5052 260 118 953 1992-10-04T20:46:15.578Z 1992-10-04T21:22:41.109Z ORB5053 173 118 953 1992-10-05T20:29:06.547Z 1992-10-05T21:03:58.555Z ORB5054 205 118 953 1992-10-06T20:07:45.492Z 1992-10-06T20:42:24.500Z ORB5055 202 118 953 1992-10-07T19:40:20.898Z 1992-10-07T20:09:54.164Z 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.