PDS_VERSION_ID                   = PDS3
RECORD_TYPE                      = FIXED_LENGTH
RECORD_BYTES                     = 8
FILE_RECORDS                     = 4193
^TABLE                           = "S9920002.B"

DATA_SET_ID                      = "LP-L-ENG-6-SUNPULSE-V1.0"
SPACECRAFT_NAME                  = "LUNAR PROSPECTOR"
PRODUCT_ID                       = "99_200_0202_0641.SUNPULSE"
MISSION_PHASE_NAME               = "EXTENDED MISSION"
TARGET_NAME                      = MOON
START_TIME                       = 1999-07-19T02:02
STOP_TIME                        = 1999-07-19T06:41
SPACECRAFT_CLOCK_START_COUNT     = 7325806
SPACECRAFT_CLOCK_STOP_COUNT      = 7334190

OBJECT                           = TABLE
  INTERCHANGE_FORMAT             = BINARY
  ROWS                           = 4193
  ROW_BYTES                      = 8
  COLUMNS                        = 4
  DESCRIPTION                    = "A sun pulse data file is a binary
    file consisting of a chronological series of sun pulse records.  The
    most recent record is at the end of the file.  Sun pulse time is
    downlinked only on even-numbered main (minor) frames.  Hence sun
    pulse file only has even-numbered spacecraft clock counts (VCDU's).

    Sun time is collected during the 2 main frames PRIOR to the
    frame in which it is downlinked.  Therefore the first main frame of
    a master frame will have values between 28 and 32 seconds, not 
    between 0 and 4 seconds as implied by the description.  All other
    frames will similarly be offset by 4 seconds."

  OBJECT                         = COLUMN
    NAME                         = SPACECRAFT_CLOCK_COUNT
    DATA_TYPE                    = MSB_BIT_STRING
    START_BYTE                   = 1
    BYTES                        = 3
    DESCRIPTION                  = "Spacecraft clock on Lunar Prospector
      is known as the VCDU counter.  It increments once every 2 seconds."
  END_OBJECT                     = COLUMN

  OBJECT                         = COLUMN
    NAME                         = SUN_PULSE_TIME
    DATA_TYPE                    = MSB_UNSIGNED_INTEGER
    START_BYTE                   = 4
    BYTES                        = 2
    DESCRIPTION                  = "Sun pulse time is measured relative
      to the master (major) frame time.  It is the number of counts from
      the first bit in the major frame header to the sun pulse.  Each
      count is 1/1800 seconds (0.0005556 seconds).  When spacecraft is
      in sunlight, this time is derived from sun sensor telemetry.  When
      spacecraft is in eclipse, this time is estimated using the history
      of spin rate change during prior shorter eclipses."
  END_OBJECT                     = COLUMN

  OBJECT                         = COLUMN
    NAME                         = TIME_UNCERTAINTY
    DATA_TYPE                    = MSB_UNSIGNED_INTEGER
    START_BYTE                   = 6
    BYTES                        = 2
    DESCRIPTION                  = "Estimated uncertainty in sun
      pulse time when spacecraft is in eclipse.  Uncertainty is
      in units of counts or 1/8000 seconds (0.0005556 seconds)."
  END_OBJECT                     = COLUMN

  OBJECT                         = COLUMN
    NAME                         = SOURCE_FLAG
    DATA_TYPE                    = UNSIGNED_INTEGER
    START_BYTE                   = 8
    BYTES                        = 1
    DESCRIPTION                  = "Flag that indicates the source of sun
      pulse time.  Value of 0 indicates that time is based on an actual
      measurement.  Value of 1 indicates that time is estimated from
      current spin rate because spacecraft is in eclipse, because there
      is a data gap in the corresponding merge file, or because pulse
      time in the corresponding merge file is inconsistent with measured
      spin period."
  END_OBJECT                     = COLUMN
END_OBJECT                       = TABLE
END