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 ---------------------------------------------------------------------------- ORB2301 571 118 953 1985-03-24T21:59:05.703Z 1985-03-24T22:58:56.883Z ORB2302 155 118 953 1985-03-25T22:16:23.156Z 1985-03-25T22:48:43.172Z ORB2303 511 118 953 1985-03-26T21:59:29.500Z 1985-03-26T22:59:20.508Z ORB2304 150 118 953 1985-03-27T22:15:33.102Z 1985-03-27T22:48:06.109Z ORB2306 572 118 953 1985-03-29T22:00:05.289Z 1985-03-29T23:00:02.500Z ORB2307 571 118 953 1985-03-30T22:00:20.977Z 1985-03-30T23:00:11.766Z ORB2308 319 118 953 1985-03-31T22:15:44.281Z 1985-03-31T22:49:13.375Z ORB2309 386 118 953 1985-04-01T22:00:49.148Z 1985-04-01T23:00:41.922Z ORB2310 572 118 953 1985-04-02T22:01:01.664Z 1985-04-02T23:00:58.906Z ORB2311 566 118 953 1985-04-03T22:01:20.977Z 1985-04-03T23:01:12.000Z ORB2312 571 118 953 1985-04-04T22:01:35.617Z 1985-04-04T23:01:26.484Z ORB2314 563 118 953 1985-04-06T22:02:04.047Z 1985-04-06T23:01:55.461Z ORB2316 25 118 953 1985-04-08T23:00:02.000Z 1985-04-08T23:02:33.125Z ORB2317 544 118 953 1985-04-09T22:02:53.711Z 1985-04-09T23:00:26.234Z ORB2318 569 118 953 1985-04-10T22:03:09.703Z 1985-04-10T23:03:00.641Z ORB2319 507 118 953 1985-04-11T22:03:26.234Z 1985-04-11T23:03:17.336Z ORB2321 562 118 953 1985-04-13T22:03:54.617Z 1985-04-13T23:03:51.867Z ORB2322 458 118 953 1985-04-14T22:07:42.227Z 1985-04-14T22:55:41.281Z ORB2323 263 118 953 1985-04-15T22:04:52.297Z 1985-04-15T23:04:24.352Z ORB2324 450 118 953 1985-04-16T22:04:45.109Z 1985-04-16T23:04:42.367Z ORB2325 568 118 953 1985-04-17T22:05:00.555Z 1985-04-17T23:04:57.812Z ORB2329 570 118 953 1985-04-21T22:06:06.570Z 1985-04-21T23:05:57.469Z ORB2330 572 118 953 1985-04-22T22:06:18.172Z 1985-04-22T23:06:15.492Z ORB2331 345 118 953 1985-04-23T22:06:33.000Z 1985-04-23T22:42:40.227Z ORB2332 568 118 953 1985-04-24T22:06:49.469Z 1985-04-24T23:06:40.570Z ORB2333 150 118 953 1985-04-25T22:07:02.984Z 1985-04-25T22:23:13.070Z ORB2334 572 118 953 1985-04-26T22:07:13.992Z 1985-04-26T23:07:11.438Z ORB2335 561 118 953 1985-04-27T22:07:29.102Z 1985-04-27T23:07:20.125Z ORB2336 572 118 953 1985-04-28T22:07:39.391Z 1985-04-28T23:07:36.914Z ORB2337 544 118 953 1985-04-29T22:07:56.758Z 1985-04-29T23:06:44.844Z ORB2338 464 118 953 1985-04-30T22:08:02.625Z 1985-04-30T22:56:39.508Z ORB2339 534 118 953 1985-05-01T22:08:15.555Z 1985-05-01T23:08:06.734Z ORB2340 552 118 953 1985-05-02T22:08:24.469Z 1985-05-02T23:08:15.555Z ORB2342 570 118 953 1985-05-04T22:08:42.125Z 1985-05-04T23:08:33.180Z ORB2343 228 118 953 1985-05-05T22:08:51.664Z 1985-05-05T22:32:41.289Z ORB2344 558 118 953 1985-05-06T22:09:00.016Z 1985-05-06T23:08:56.945Z ORB2347 361 118 953 1985-05-09T22:09:24.242Z 1985-05-09T23:09:15.266Z ORB2348 569 118 953 1985-05-10T22:09:27.484Z 1985-05-10T23:09:18.508Z ORB2349 483 118 953 1985-05-11T22:14:43.555Z 1985-05-11T23:09:25.969Z ORB2350 530 118 953 1985-05-12T22:09:39.086Z 1985-05-12T23:09:29.953Z ORB2351 571 118 953 1985-05-13T22:09:42.016Z 1985-05-13T23:09:33.031Z ORB2352 219 118 953 1985-05-14T22:09:47.062Z 1985-05-14T22:36:21.219Z ORB2353 549 118 953 1985-05-15T22:09:49.742Z 1985-05-15T23:09:40.766Z ORB2356 572 118 953 1985-05-18T22:09:51.305Z 1985-05-18T23:09:48.625Z ORB2358 402 118 953 1985-05-20T22:22:01.031Z 1985-05-20T23:09:47.172Z ORB2360 498 118 953 1985-05-22T22:09:50.414Z 1985-05-22T23:09:48.031Z ORB2361 197 118 953 1985-05-23T22:09:47.742Z 1985-05-23T22:30:22.688Z ORB2362 560 118 953 1985-05-24T22:09:47.016Z 1985-05-24T23:09:44.648Z ORB2363 563 118 953 1985-05-25T22:09:48.719Z 1985-05-25T23:09:39.805Z ORB2364 564 118 953 1985-05-26T22:09:45.711Z 1985-05-26T23:09:36.836Z ORB2365 515 118 953 1985-05-27T22:09:43.711Z 1985-05-27T23:09:34.891Z ORB2366 414 118 953 1985-05-28T22:09:36.938Z 1985-05-28T23:03:22.086Z ORB2368 552 118 953 1985-05-30T22:09:58.109Z 1985-05-30T23:09:49.203Z ORB2369 569 118 953 1985-05-31T22:09:53.898Z 1985-05-31T23:09:45.547Z ORB2370 559 118 953 1985-06-01T22:09:51.039Z 1985-06-01T23:09:41.484Z ORB2371 531 118 953 1985-06-02T22:09:46.789Z 1985-06-02T23:09:38.031Z 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.