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 ---------------------------------------------------------------------------- ORB4900 319 118 953 1992-05-05T23:31:41.789Z 1992-05-06T01:28:16.330Z ORB4901 784 118 953 1992-05-06T23:29:37.258Z 1992-05-07T01:28:47.304Z ORB4909 902 118 953 1992-05-14T23:31:13.445Z 1992-05-15T01:05:55.981Z ORB4910 910 118 953 1992-05-15T23:31:02.898Z 1992-05-16T01:30:19.942Z ORB4911 1078 118 953 1992-05-16T23:31:16.422Z 1992-05-17T01:25:11.962Z ORB4912 1130 118 953 1992-05-17T23:31:44.438Z 1992-05-18T01:30:35.986Z ORB4913 572 118 953 1992-05-18T23:31:10.469Z 1992-05-19T00:35:55.930Z ORB4914 1047 118 953 1992-05-19T23:32:20.484Z 1992-05-20T01:24:54.029Z ORB4915 1023 118 953 1992-05-20T23:32:28.445Z 1992-05-21T01:19:59.988Z ORB4916 1023 118 953 1992-05-21T23:32:24.477Z 1992-05-22T01:20:08.518Z ORB4917 1065 118 953 1992-05-22T23:32:00.508Z 1992-05-23T01:25:18.550Z ORB4918 128 118 953 1992-05-23T23:32:30.539Z 1992-05-23T23:46:53.547Z ORB4919 533 118 953 1992-05-24T23:32:55.578Z 1992-05-25T01:24:51.120Z ORB4920 801 118 953 1992-05-25T23:32:36.109Z 1992-05-26T01:25:16.155Z ORB4921 935 118 953 1992-05-26T23:32:35.641Z 1992-05-27T01:31:39.192Z ORB4922 973 118 953 1992-05-27T23:33:06.680Z 1992-05-28T01:24:37.724Z ORB4923 1086 118 953 1992-05-28T23:32:39.719Z 1992-05-29T01:31:50.266Z ORB4924 644 118 953 1992-05-29T23:33:08.258Z 1992-05-30T01:04:10.791Z ORB4925 398 118 953 1992-05-30T23:33:52.797Z 1992-05-31T00:37:07.070Z ORB4961 234 118 953 1992-07-05T23:54:47.719Z 1992-07-06T01:13:11.745Z ORB4962 68 118 953 1992-07-07T00:22:08.226Z 1992-07-07T00:30:07.228Z ORB4963 75 118 953 1992-07-08T00:22:07.203Z 1992-07-08T00:29:53.706Z ORB4964 311 118 953 1992-07-08T23:33:02.664Z 1992-07-09T01:25:48.204Z ORB4965 928 118 953 1992-07-09T23:26:33.148Z 1992-07-10T01:03:53.184Z ORB4966 1121 118 953 1992-07-10T23:28:16.641Z 1992-07-11T01:25:52.685Z ORB4967 244 118 953 1992-07-11T23:45:16.141Z 1992-07-12T01:25:07.677Z ORB4968 182 118 953 1992-07-12T23:56:34.125Z 1992-07-13T00:54:36.646Z ORB4969 188 118 953 1992-07-13T23:57:10.609Z 1992-07-14T00:54:30.629Z ORB4970 185 118 953 1992-07-14T23:58:36.086Z 1992-07-15T00:54:16.109Z ORB4971 176 118 953 1992-07-15T23:56:42.555Z 1992-07-16T00:54:02.579Z ORB4972 120 118 953 1992-07-16T23:55:37.031Z 1992-07-17T00:53:49.048Z ORB4973 531 118 953 1992-07-17T23:54:56.000Z 1992-07-18T00:54:09.022Z ORB4975 523 118 953 1992-07-19T23:54:32.461Z 1992-07-20T00:53:45.483Z ORB4976 181 118 953 1992-07-20T23:54:54.945Z 1992-07-21T00:53:22.967Z ORB4977 177 118 953 1992-07-21T23:55:35.930Z 1992-07-22T00:52:55.946Z ORB4978 77 118 953 1992-07-23T00:18:40.908Z 1992-07-23T00:26:39.411Z ORB4979 504 118 953 1992-07-23T23:53:37.383Z 1992-07-24T00:53:15.905Z ORB4980 425 118 953 1992-07-24T23:53:28.867Z 1992-07-25T00:53:06.893Z ORB4983 77 118 953 1992-07-28T00:18:03.792Z 1992-07-28T00:26:02.294Z ORB4985 257 118 953 1992-07-30T00:18:05.221Z 1992-07-30T00:52:34.231Z ORB4986 261 118 953 1992-07-31T00:17:48.185Z 1992-07-31T00:52:23.695Z ORB4987 269 118 953 1992-08-01T00:17:37.653Z 1992-08-01T00:52:30.164Z ORB4988 265 118 953 1992-08-02T00:17:49.117Z 1992-08-02T00:52:25.127Z ORB4989 261 118 953 1992-08-03T00:17:43.581Z 1992-08-03T00:52:24.092Z ORB4990 259 118 953 1992-08-04T00:17:41.050Z 1992-08-04T00:52:15.061Z ORB4991 263 118 953 1992-08-05T00:17:33.511Z 1992-08-05T00:52:20.023Z ORB4994 254 118 953 1992-08-08T00:17:45.896Z 1992-08-08T00:52:19.908Z ORB4995 219 118 953 1992-08-09T00:14:11.328Z 1992-08-09T00:52:18.365Z ORB4996 266 118 953 1992-08-10T00:13:25.751Z 1992-08-10T00:52:16.763Z ORB4997 28 118 953 1992-08-11T00:23:18.638Z 1992-08-11T00:27:33.619Z ORB4998 253 118 953 1992-08-12T00:17:51.356Z 1992-08-12T00:52:20.367Z ORB4999 261 118 953 1992-08-13T00:17:28.815Z 1992-08-13T00:52:28.327Z 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.