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 <bits/sec>
LAT float Venusian Latitude <deg>
LON float Venusian Longitude <deg>
ALT float Altitude <km>
SZA float Solar Zenith Angle <deg>
SHA float Solar Hour Angle <hr>
MASS1 int Mass of Sample 1 <AMU>
DEN1 float Number density of Sample 1 <ions/cm^3>
MASS2 int Mass of Sample 2 <AMU>
DEN2 float Number density of Sample 2 <ions/cm^3>
. . .
. . .
. . .
MASS55 int Mass of Sample 55 <AMU>
DEN55 float Number density of Sample 55 <ions/cm^3>
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
----------------------------------------------------------------------------
ORB0800 218 118 953 1981-02-12T23:45:16.164Z 1981-02-13T00:29:27.182Z
ORB0801 201 118 953 1981-02-13T23:46:24.250Z 1981-02-14T00:07:55.776Z
ORB0802 201 118 953 1981-02-14T23:47:32.000Z 1981-02-15T00:10:12.886Z
ORB0804 201 118 953 1981-02-16T23:49:53.852Z 1981-02-17T00:22:18.615Z
ORB0805 218 118 953 1981-02-17T23:51:06.219Z 1981-02-18T00:26:54.648Z
ORB0807 201 118 953 1981-02-19T23:53:18.211Z 1981-02-20T00:14:18.303Z
ORB0808 218 118 953 1981-02-20T23:54:30.062Z 1981-02-21T00:31:07.060Z
ORB0809 218 118 953 1981-02-21T23:55:36.320Z 1981-02-22T00:40:31.450Z
ORB0810 201 118 953 1981-02-22T23:56:44.906Z 1981-02-23T00:17:51.311Z
ORB0811 218 118 953 1981-02-23T23:58:02.164Z 1981-02-24T00:23:39.180Z
ORB0868 32 118 953 1981-04-22T01:17:19.067Z 1981-04-22T02:09:27.086Z
ORB0873 122 118 953 1981-04-27T01:23:59.378Z 1981-04-27T02:03:03.396Z
ORB0874 168 118 953 1981-04-28T01:27:00.818Z 1981-04-28T02:25:06.092Z
ORB0875 197 118 953 1981-04-29T01:26:52.707Z 1981-04-29T02:11:06.725Z
ORB0876 201 118 953 1981-04-30T01:28:32.850Z 1981-04-30T02:16:15.119Z
ORB0877 201 118 953 1981-05-01T01:30:00.739Z 1981-05-01T02:08:11.387Z
ORB0878 218 118 953 1981-05-02T01:31:27.074Z 1981-05-02T01:56:58.636Z
ORB0879 218 118 953 1981-05-03T01:32:54.508Z 1981-05-03T02:12:40.103Z
ORB0880 201 118 953 1981-05-04T01:34:20.633Z 1981-05-04T01:56:35.838Z
ORB0881 201 118 953 1981-05-05T01:35:39.956Z 1981-05-05T01:56:39.766Z
ORB0883 201 118 953 1981-05-07T01:38:31.245Z 1981-05-07T02:16:20.011Z
ORB0884 218 118 953 1981-05-08T01:38:29.850Z 1981-05-08T02:18:01.560Z
ORB0885 201 118 953 1981-05-09T01:38:26.357Z 1981-05-09T02:05:57.973Z
ORB0886 201 118 953 1981-05-10T01:38:31.570Z 1981-05-10T02:16:47.527Z
ORB0888 218 118 953 1981-05-12T01:38:16.023Z 1981-05-12T02:18:55.515Z
ORB0889 218 118 953 1981-05-13T01:38:11.318Z 1981-05-13T02:09:03.112Z
ORB0890 188 118 953 1981-05-14T01:38:04.722Z 1981-05-14T02:37:55.746Z
ORB0892 201 118 953 1981-05-16T01:37:51.415Z 1981-05-16T02:00:03.113Z
ORB0893 201 118 953 1981-05-17T01:37:44.613Z 1981-05-17T01:58:44.525Z
ORB0894 218 118 953 1981-05-18T01:37:34.208Z 1981-05-18T02:02:58.090Z
ORB0895 218 118 953 1981-05-19T01:37:28.705Z 1981-05-19T02:16:51.207Z
ORB0896 201 118 953 1981-05-20T01:37:17.198Z 1981-05-20T01:59:49.058Z
ORB0897 218 118 953 1981-05-21T01:37:14.141Z 1981-05-21T02:17:42.615Z
ORB0898 201 118 953 1981-05-22T01:37:04.980Z 1981-05-22T02:13:55.577Z
ORB0899 201 118 953 1981-05-23T01:36:48.022Z 1981-05-23T01:59:18.333Z
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.