Data Set Overview
=================
    The TVS data from KFKI came in various stages.  The
    initial submission from KFKI was completely replaced
    in the fall 1992.  At that time, additional processed
    data with aspect and range corrections were included.
     The original filenaming scheme was preserved except
    for changing the leading filename character and
    expressing the aspect ratio as 'a'.
 
 
Mission  data description                 KFKI      New       LPL-NO
 
Vega 1   original 63 images               w01114    T01114    1114
         filtered 32 images               w02114    T02114    2114
         filtered with 4/3 aspect corr    w211443   T2114A
         filtered, aspect and range corr  w211443r  T2114AR
         sharpened 32 images              w09114    T09114    9114
         sharpened with 4/3 aspect corr   w911443   T9114A
         sharpened, aspect and range corr w911443r  T9114AR
         flat field                       w02769    T02769    2769
Vega 2   original 11 images               w01174    T01174    1174
         filtered 11 images               w11174    T11174    2174
         flat fields                      w01301    T01301
 
 
 
Vega 2 Data:
 
     Later submissions included the images from March 7
    (189) and March 10 (51) before and after the
    encounter period (March 9 (7:20:54.8), 1986).  These
    data were given a file description to indicate if
    they were PRE or POST encounter.  The data, in its
    original form, is included but with a new filenaming
    scheme which was unique to the data set.  The data
    were sent as a separate image file (8 bit) with an
    ascii description of the header information.  An
    IHW-FITS file was created from this data in the style
    of the previous submissions, and approximate times
    was calculated from the TONBHRDW value provided with
    the data.  Since this is a relative value, the
    switch-on time was taken from a preprint by Laszlo
    Varhalmi (KFKI) and a previous communication with
    KFKI also gave the state vector for each spacecraft
    during the encounter.  Note that the switch-on times
    are then given as UT = Moscow time - 3 hours.  and a
    'light travel time' must be subtracted to match
    published times.  The algorithm for the midpoint of
    any exposure was calculated as follows:
 
 
UT (midpoint)
    = UT0+5.5+TONBHRDW/4.766485-T(exp)-T(loc)+T(exp)/2  (second).
 
 
    Note the clock count rate is assumed to be the same
    as for Vega 1 data.  We have taken the 5.5 s
    correction from Varhalmi as due to a memory readout;
    another correction of 1.6 s called T (loc) was needed
    if the image was less than the full array which is a
    process time to find and transmit the data.  For Vega
    2, the assumed switch-on times (UT0) were March 7,
    3h47m25s and for March 10, 5h48m14s; these values are
    given as COMMENTs in the FITS header.  The state
    vectors for Vega 2 in equatorial XYZ coordinates are
    as follows:
 
 
    X=-63031872.6   Y=-107676032.6   Z=+1048764.   (in km)
    V(X)=+31.6486   V(Y)=-11.6669    V(Z)=-1.8879   (in km/sec)
 
 
    It was asuumed these were barycentric coordinates and
    the linear velocities were used to estimate the
    coordinates for the new dates and times.  Appropriate
    values from the Nautical Almanac for 1986 were used
    to make the earth correction and eventually subtract
    the light travel time correction.  It was determined
    that the calculated UT times are consistent with the
    published values within 3 seconds; as such we leave
    the TIME-OBS keyword value (midpoint day fraction
    required by the IHW) as 4 significant digits.
 
     For two of the filtered files, the submitted FITS
    header had errors in the TONBHRDW values; these were
    eliminated.  In the case of 5 other files (1198,
    1202, 1206, 1210, 1214), no FITS information was
    sent; the FITS header was constructed from the
    corresponding original data file except that a
    CHECKSUM value was added to identify the image
    correctly.
 
     Abergel, J., Bertaux, G., Avanessov, G.A.,
    Tarnopolsky, V.I., and Zhulov, B.S., 1987, Appl.
     Opt., 26, No.26, 4457-4468.
 
     Kondor, A., 1990, MPAE-W-100-90-04.
 
     Merenyi, E., Foldy, C., Szego, K., Toth, I.  and
    Kondor, A., 1990, Icarus, 86, 9-20.

Confidence Level Overview
========================
 
 N/A