PDS_VERSION_ID               = PDS3

/* File Characteristics */

RECORD_TYPE                  = FIXED_LENGTH
RECORD_BYTES                 = 52
FILE_RECORDS                 = 792

/* Data Object Pointers */

^TABLE                       = "STMODEL.TAB"

/* Identification Keywords */

DATA_SET_ID                  = "IRAS-A-FPA-3-RDR-IMPS-V4.0"
PRODUCT_NAME                 = "IMPS Standard Thermal Model Flux Table"
PRODUCT_ID                   = "IMPS-STMODEL-199803"
INSTRUMENT_HOST_NAME         = "INFRARED ASTRONOMICAL SATELLITE"
INSTRUMENT_NAME              = "FOCAL PLANE ARRAY"
TARGET_NAME                  = ASTEROID
START_TIME                   = 1983-01
STOP_TIME                    = 1983-11
PRODUCT_CREATION_TIME        = 1998-03-23  /* Peer Review Date */
RECORD_FORMAT                = "(f4.1,1x,f4.2,4(1x,e9.3))"
OBJECT                       = TABLE
 ROWS                        = 792
 ROW_BYTES                   = 52
 INTERCHANGE_FORMAT          = ASCII
 COLUMNS                     = 6
 DESCRIPTION                 = "This product represents the flux look-up
table used to derive a geometric albedo given a heliocentric distance and
Bond albedo. This table was provided by L. Lebofsky and was derived from the
IRAS standard thermal model in LEBOFSKYETAL1986A and LEBOFSKYETAL1986B.
Fluxes (Watts/m^2) in each of the four IRAS passbands are given for a
hypothetical asteroid with a radius of 1 km located 1 AU from the spacecraft.

In general, a value was initially assumed for the geometric albedo. The Bond
albedo was then calculated by multiplying the geometric albedo by an
estimated phase integral. Using this information and the asteroid absolute
magnitude, an estimate of the asteroid radius was made.  The flux was then
interpolated in the thermal model table. The interpolation was linear in
albedo and quadratic in heliocentric distance; the flux was then scaled for
the current estimate of the radius and the distance from the spacecraft to
the asteroid, and the phase angle correction was applied as discussed in
TEDESCOETAL1992 (Section 4.3.4.C). The model flux was then compared to the
observed flux and the geometric albedo was adjusted accordingly. The process
was repeated until the observed and model fluxes converged. This yielded the
radiometric geometric albedo and radius for the given asteroid."


 OBJECT                      = COLUMN
  COLUMN_NUMBER              = 1
  NAME                       = "HELIOCENTRIC DISTANCE"
  DESCRIPTION                = "The distance between the asteroid and Sun."
  DATA_TYPE                  = ASCII_REAL
  UNIT                       = "AU"
  START_BYTE                 = 1
  BYTES                      = 4
  FORMAT                     = "F4.1"
 END_OBJECT                  = COLUMN

 OBJECT                      = COLUMN
  COLUMN_NUMBER              = 2
  NAME                       = "BOLOMETRIC BOND ALBEDO"
  DESCRIPTION                = "The bolometric Bond albedo."
  DATA_TYPE                  = ASCII_REAL
  START_BYTE                 = 6
  BYTES                      = 4
  FORMAT                     = "F4.2"
 END_OBJECT                  = COLUMN

 OBJECT                      = COLUMN
  COLUMN_NUMBER              = 3
  NAME                       = "STM 12 MICRON FLUX DENSITY"
  DESCRIPTION                = "IRAS standard thermal model flux at
12 microns."
  DATA_TYPE                  = ASCII_REAL
  START_BYTE                 = 11
  BYTES                      = 9
  FORMAT                     = "E9.3"
 END_OBJECT                  = COLUMN

 OBJECT                      = COLUMN
  COLUMN_NUMBER              = 4
  NAME                       = "STM 25 MICRON FLUX DENSITY"
  DESCRIPTION                = "IRAS standard thermal model flux at
25 microns."
  DATA_TYPE                  = ASCII_REAL
  START_BYTE                 = 21
  BYTES                      = 9
  FORMAT                     = "E9.3"
 END_OBJECT                  = COLUMN

 OBJECT                      = COLUMN
  COLUMN_NUMBER              = 5
  NAME                       = "STM 60 MICRON FLUX DENSITY"
  DESCRIPTION                = "IRAS standard thermal model flux at
60 microns."
  DATA_TYPE                  = ASCII_REAL
  START_BYTE                 = 31
  BYTES                      = 9
  FORMAT                     = "E9.3"
 END_OBJECT                  = COLUMN

 OBJECT                      = COLUMN
  COLUMN_NUMBER              = 6
  NAME                       = "STM 100 MICRON FLUX DENSITY"
  DESCRIPTION                = "IRAS standard thermal model flux at
100 microns."
  DATA_TYPE                  = ASCII_REAL
  START_BYTE                 = 41
  BYTES                      = 9
  FORMAT                     = "E9.3"
 END_OBJECT                  = COLUMN

END_OBJECT                   = TABLE
END