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 ---------------------------------------------------------------------------- ORB3531 1100 118 953 1988-08-06T01:41:42.326Z 1988-08-06T03:40:59.121Z ORB3533 1357 118 953 1988-08-08T01:42:05.599Z 1988-08-08T03:13:26.633Z ORB3535 848 118 953 1988-08-10T02:35:24.618Z 1988-08-10T03:41:58.415Z ORB3536 521 118 953 1988-08-11T02:35:22.848Z 1988-08-11T03:42:15.402Z ORB3537 470 118 953 1988-08-12T02:35:58.603Z 1988-08-12T03:31:18.146Z ORB3539 911 118 953 1988-08-14T01:43:34.365Z 1988-08-14T03:19:13.899Z ORB3540 1124 118 953 1988-08-15T01:44:06.379Z 1988-08-15T03:43:29.423Z ORB3542 613 118 953 1988-08-17T02:38:46.920Z 1988-08-17T03:44:24.444Z ORB3543 621 118 953 1988-08-18T02:38:42.929Z 1988-08-18T03:44:45.953Z ORB3544 2030 118 953 1988-08-19T01:45:54.921Z 1988-08-19T03:45:05.465Z ORB3545 1127 118 953 1988-08-20T01:45:50.938Z 1988-08-20T03:45:26.481Z ORB3547 2254 118 953 1988-08-22T01:46:59.966Z 1988-08-22T03:46:10.510Z ORB3548 1139 118 953 1988-08-23T01:46:56.981Z 1988-08-23T03:46:33.025Z ORB3550 76 118 953 1988-08-25T02:40:42.005Z 1988-08-25T02:52:30.774Z ORB3551 779 118 953 1988-08-26T01:48:18.015Z 1988-08-26T03:09:59.544Z ORB3552 2272 118 953 1988-08-27T01:48:47.530Z 1988-08-27T03:48:04.573Z ORB3553 68 118 953 1988-08-28T01:48:45.530Z 1988-08-28T01:55:54.032Z ORB3554 978 118 953 1988-08-29T01:48:48.044Z 1988-08-29T03:48:22.085Z ORB3556 952 118 953 1988-08-31T02:45:10.027Z 1988-08-31T03:49:05.069Z ORB3558 674 118 953 1988-09-02T01:50:30.202Z 1988-09-02T03:15:37.730Z ORB3560 1137 118 953 1988-09-04T01:51:02.218Z 1988-09-04T03:50:37.764Z ORB3561 2268 118 953 1988-09-05T01:51:36.242Z 1988-09-05T03:50:59.787Z ORB3563 930 118 953 1988-09-07T02:45:03.532Z 1988-09-07T03:51:45.327Z ORB3564 569 118 953 1988-09-08T02:45:09.045Z 1988-09-08T03:52:01.851Z ORB3566 2274 118 953 1988-09-10T01:53:22.335Z 1988-09-10T03:52:45.379Z ORB3567 1137 118 953 1988-09-11T01:53:22.857Z 1988-09-11T03:52:58.401Z ORB3568 520 118 953 1988-09-12T02:47:04.129Z 1988-09-12T03:53:26.421Z ORB3569 1139 118 953 1988-09-13T01:54:14.879Z 1988-09-13T03:53:44.425Z ORB3570 556 118 953 1988-09-14T02:48:05.652Z 1988-09-14T03:54:01.943Z ORB3571 157 118 953 1988-09-15T02:47:40.400Z 1988-09-15T03:39:57.684Z ORB3573 151 118 953 1988-09-17T01:55:30.158Z 1988-09-17T02:19:07.666Z ORB3574 802 118 953 1988-09-18T01:56:15.154Z 1988-09-18T04:03:40.700Z ORB3575 730 118 953 1988-09-19T01:56:22.417Z 1988-09-19T03:55:26.210Z ORB3576 755 118 953 1988-09-20T01:56:28.428Z 1988-09-20T03:55:41.971Z ORB3577 406 118 953 1988-09-21T02:49:36.160Z 1988-09-21T03:55:54.951Z ORB3578 394 118 953 1988-09-22T02:49:41.916Z 1988-09-22T03:56:09.715Z ORB3579 712 118 953 1988-09-23T01:57:41.685Z 1988-09-23T03:56:26.728Z ORB3580 747 118 953 1988-09-24T01:57:26.663Z 1988-09-24T03:56:40.204Z ORB3581 756 118 953 1988-09-25T01:57:58.673Z 1988-09-25T03:56:53.467Z ORB3582 557 118 953 1988-09-26T01:58:02.935Z 1988-09-26T03:56:20.227Z ORB3583 468 118 953 1988-09-27T01:58:03.192Z 1988-09-27T03:57:16.736Z ORB3584 246 118 953 1988-09-28T02:50:49.933Z 1988-09-28T03:57:17.729Z ORB3585 73 118 953 1988-09-29T02:51:37.704Z 1988-09-29T03:02:57.947Z ORB3586 73 118 953 1988-09-30T02:51:48.207Z 1988-09-30T03:03:09.198Z ORB3587 752 118 953 1988-10-01T01:59:02.210Z 1988-10-01T03:57:57.002Z ORB3588 713 118 953 1988-10-02T01:59:20.464Z 1988-10-02T03:51:28.754Z ORB3590 758 118 953 1988-10-04T01:59:07.719Z 1988-10-04T03:58:21.261Z ORB3591 238 118 953 1988-10-05T02:51:51.701Z 1988-10-05T03:58:28.495Z ORB3592 118 118 953 1988-10-06T02:52:35.781Z 1988-10-06T03:58:35.004Z ORB3593 537 118 953 1988-10-07T01:59:17.688Z 1988-10-07T03:58:40.979Z ORB3594 657 118 953 1988-10-08T01:59:12.947Z 1988-10-08T03:51:21.237Z ORB3595 492 118 953 1988-10-09T02:00:05.208Z 1988-10-09T03:58:50.249Z ORB3596 720 118 953 1988-10-10T01:59:59.716Z 1988-10-10T03:57:38.759Z ORB3597 675 118 953 1988-10-11T01:59:44.938Z 1988-10-11T03:58:58.481Z ORB3598 733 118 953 1988-10-12T01:59:48.441Z 1988-10-12T03:59:01.984Z ORB3599 1150 118 953 1988-10-13T02:02:29.946Z 1988-10-13T04:32:59.000Z 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.